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BACKGROUND: Epilepsy is a chronic neurological disorder affecting more than 50 million people worldwide, of whom 80% live in low- and middle-income countries. Due to the limited availability of antiseizure drugs (ASDs) in these countries, medicinal plants are the first-line treatment for most epilepsy patients. In Cameroon, a decoction of Cyperus articulatus L. rhizomes is traditionally used to treat epilepsy. PURPOSE: The aim of this study was to identify and isolate the active compounds responsible for the antiseizure activity of C. articulatus in order to confirm both its traditional medicinal usage and previous in vivo studies on extracts of this plant in mouse epilepsy models. METHODS: The dried rhizomes of C. articulatus were extracted with solvents of increasing polaritie (hexane, dichloromethane, methanol and water). A traditional decoction and an essential oil were also prepared. These extracts were evaluated for antiseizure activity using a larval zebrafish seizure model with seizures induced by the GABAA antagonist pentylenetetrazole (PTZ). The hexane extract demonstrated the highest antiseizure activity and was therefore selected for bioassay-guided fractionation. The isolated bioactive compounds were characterized by classical spectroscopic methods. Since they were found to be volatile, they were quantified by GC-FID. In addition, the absorption of the active compounds through the gastrointestinal tract and the blood-brain barrier was evaluated using a hexadecane and a blood-brain barrier parallel artificial membrane permeability assays (HDM-PAMPA and PAMPA-BBB). RESULTS: The hexane extract of C. articulatus exhibited the highest antiseizure activity with a reduction of 93% of PTZ-induced seizures, and was therefore subjected to bioassay-guided fractionation in order to isolate the active principles. Four sesquiterpenoids were identified as cyperotundone (1), mustakone (2), 1,2-dehydro-α-cyperone (3) and sesquichamaenol (4) and exhibited significant antiseizure activity. These volatile compounds were quantified by GC in the hexane extract, the essential oil and the simulated traditional decoction. In addition, the constituents of the hexane extract including compounds 1 and 2 were found to cross the gastrointestinal barrier and the major compound 2 crossed the blood-brain barrier as well. CONCLUSION: These results highlight the antiseizure activity of various sesquiterpene compounds from a hexane extract of C. articulatus dried rhizomes and support its use as a traditional treatment for epilepsy.

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STATEMENT OF PROBLEM: With the emergence of digital technologies, new materials have become available for occlusal devices. However, data are scarce about these different materials and technologies and their mechanical properties. PURPOSE: The purpose of this in vitro study was to investigate the flexural strength and surface hardness of different materials using different technologies for occlusal device fabrication, with an emphasis on the digital technologies of computer-aided design and computer-aided manufacturing (CAD-CAM) and 3D printing. MATERIAL AND METHODS: A total of 140 rectangular specimens were fabricated from two 3D-printed (VarseoWax Splint and Ortho Rigid), 2 CAD-CAM-produced (Ceramill Splintec and CopraDur), and 3 conventional autopolymerizing occlusal device materials (ProBase Cold, Resilit S, and Orthocryl) according to ISO 20795-1:2013. Flexural strength and surface hardness were determined for 10 specimens of each tested material using the 3-point bend test and the Brinell method. The data were analyzed using descriptive statistics and 1-way ANOVA with Bonferroni corrections (α=.05). RESULTS: Surface hardness values ranged from 28.5 ±2.5 MPa to 116.2 ±1.6 MPa. During flexural testing, neither the CopraDur nor the VarseoWax Splint specimens fractured during loading within the end limits of the penetrant's possible movement. Flexural strength values for other groups ranged from 75.0 ±12.0 MPa to 104.9 ±6.2 MPa. Statistical analysis determined significant differences among the tested materials for flexural strength and surface hardness. CONCLUSIONS: Mechanical properties among different occlusal device materials were significantly different. Acrylic resins were less flexible than polyamide and nonacrylic occlusal device materials for 3D printing but had higher and more consistent values of surface hardness. Clinicians should consider the different mechanical properties of the available materials when choosing occlusal device materials.

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Plants which have been traditionally eaten by alpine populations may provide new opportunities of agricultural development for mountain regions. In this context we investigated the chemical composition of Cirsium spinosissimum (Asteraceae), a perennial thistle. Its receptacles were eaten by shepherds in Valais (Switzerland). Extracts of aerial parts were subjected to a comprehensive metabolite profiling, using a dereplication platform, combining HPLC-PDA-MS and offline microprobe NMR analysis. Twenty compounds, including various phenolic glycosides, a monoterpene lactone, a spermine derivative, and fatty acids, could be identified online, or after targeted isolation. The total phenolic content was determined, and the major flavonoids were quantitatively assessed in fresh receptacles by HPLC-PDA analysis. In addition, substances relevant for nutrition, such as ß-carotene, fatty acids, ascorbic acid, and minerals, were quantified. The ethanolic extract of the receptacles showed no sign of cytotoxicity when tested in Caco-2 cells.

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Plants which have been traditionally eaten by the alpine population may provide new opportunities for agricultural development in mountain regions. In this context we have investigated the chemical composition of Phyteuma orbiculare (Campanulaceae), a perennial herb whose leaves have been eaten as salad by rural populations in Valais (Switzerland). Extracts of different polarities were subjected to comprehensive metabolite profiling using a dereplication platform combining HPLC-PDA-MS, and offline NMR analysis. Twenty-three compounds, including various phenolic glycosides, a new dimeric phenylpropanoid glucoside, saponins, and fatty acids were identified online, or after targeted isolation. Selected phenolic constituents were quantitatively assessed by HPLC-PDA analysis. In addition, substances relevant for nutrition, such as ß-carotene, fatty acids, ascorbic acid and minerals were quantified in leaves and flowers. The antioxidant capacity was determined with an ORAC assay, and total phenolic compounds were quantified. Finally, the phytochemical profile was compared to that of the related species P. spicatum, P. hemisphaericum and P. ovatum.

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The ability of two plant extracts, Rheum palmatum root extract (RPRE) and Frangula alnus bark extract (FABE), to protect Vitis vinifera leaves from Plasmopara viticola infection was evaluated. These natural products are toxic to the pathogen and induce defence reactions in a susceptible cultivar of V. vinifera (V. vinifera cv. Chasselas), including stilbenic phytoalexin accumulation, enhanced peroxidase (EC 1.11.1.7) activity, and a hypersensitive reaction. Inhibition of the first stage of biotrophic hyphal development of P. Viticola by the two plant extracts was observed. HPLC-DAD-MS analysis showed that these two natural extracts contain many phenolic compounds belonging to the anthraquinone family, such as rhein, frangulin A, emodin, aloe-emodin, chrysophanol, and physcion. Emodin alone is able to impair P. viticola development and to stimulate viniferins and the accumulation of pterostilbene.

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