Fatty acid composition in matrix vesicles and in microvilli from femurs of chicken embryos revealed selective recruitment of fatty acids.

Hypertrophic chondrocytes participate in matrix mineralization by releasing matrix vesicles (MVs). These MVs, by accumulating Ca(2+) and phosphate initiate the formation of hydroxyapatite. To determine the types of lipids essential for mineralization, we analyzed fatty acids (FAs) in MVs, microvilli and in membrane fractions of chondrocytes isolated from femurs of chicken embryos. The FA composition in the MVs was almost identical to that in microvilli, indicating that the MVs originated from microvilli. These fractions contained more monounsaturated FAs especially oleic acid than in membrane homogenates of chondrocytes. They were enriched in 5,8,11-eicosatrienoic acid (20:3n-9), in eicosadienoic acid (20:2n-6), and in arachidonic acid (20:4n-6). In contrast, membrane homogenates from chondrocytes were enriched in 20:1n-9, 18:3n-3, 22:5n-3 and 22:5n-6. Due to their relatively high content in MVs and to their selective recruitment within microvilli from where MV originate, we concluded that 20:2n-6 and 20:3n-9 (pooled values), 18:1n-9 and 20:4n-6 are essential for the biogenesis of MVs and for bone mineralization.

Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras

Objective:To determine the chemical composition, total phenolic and total flavonoid contents of the crude extracts from leaves and stems of a Lebanese plant Euphorbia macroclada schyzoceras (E. macroclada), and to evaluate their antioxidant potential using DPPH, H2O2, and chelating of ferrous ions tests. Methods:Quantification of the total phenolic and total flavonoid contents of the crude extracts from leaves and stems and the antioxidant activities were evaluated using spectrophotometric analyses. The chemical composition has been estimated using different techniques such as IR, LC/MS and NMR. Results:Ethanolic extract from leaves of E. macroclada was better than aqueous extract and showed higher content in total phenolic and total flavonoid than found in the stems. On the other hand, using DPPH and H2O2 tests, this extract from leaves showed higher antioxidant capacity than aqueous extract. However, using the chelating of ferrous ions test, the antioxidant activity of the aqueous extract of both stems and leaves was stronger than that of ethanolic once. The chemical composition of the whole plant showed the presence of some aromatic compounds and fatty acids. Conclusions:Both ethanolic and water extracts from both parts of this plant are effective and have good antioxidant power. So, this plant can be used in the prevention of a number of diseases related to oxidative stress.

Phytochemical screening and antioxidant activity of Lebanese Eryngium creticum L

Objective: To determine the phytochemical screening and quantification of total phenolics contents in fresh Eryngium creticum (E. creticum) leaves and stems extract and to evaluate its total antioxidant activity. Methods: Quantification of total phenolics contents in fresh E. creticum leaves and stems extract and evaluation of its total antioxidant activity, were done using the spectrophotometric analyses. Results: The consumption of 100 g of fresh E. creticum leaves and stems could provide antioxidants equivalent to (78.50±0.80) mg of vitamin C and (50.42±0.50) mg of vitamin C, respectively. Conclusions: From this study, it can be concluded that E. creticum can be interesting to prevent diseases directly linked to oxidative stress.

Chemical composition, in vitro cytotoxicity and anti-free radical properties of six extracts from Lebanese Trigonella berythea Boiss

This study represents an original work aimed to recognize the main constitution of Trigonella berythea. The total phenolic content and total flavonoid content of leaves and stems of T. berythea have been estimated. An extraction and purification of phenolic mixture compounds from the leaves and stems of this plant have been performed and their antioxidant potential using the DPPH, H[2]O[2] and chelating of ferrous ions tests has been evaluated. Then, their cytotoxicity on the MCF7 breast cancer cell line by the XTT Cell Viability technique has been studied. Our results demonstrated that leaves of T. berythea had higher total phenolic content and total flavonoid content than stems. On the other hand, the six extract from leaves and stems of this plant demonstrated a high antioxidant potential reaches more than 80%. Also, extracts from leaves of T. berythea had the highest inhibitory effect on MCF7 and U937 cell growth than that of stems. This inhibition was more than 60% for all extracts. These results provide new insight into the health functions of leaves and stems and demonstrate that T. berythea extracts can potentially have health benefits

Replacement of the Alpha variant of SARS-CoV-2 by the Delta variant in Lebanon between April and June 2021

BackgroundThe COVID-19 pandemic continues to expand globally, with case numbers rising in many areas of the world, including the Eastern Mediterranean Region. Lebanon experienced its largest wave of COVID-19 infections from January to April 2021. Limited genomic surveillance was undertaken, with just twenty six SARS-CoV-2 genomes available for this period, nine of which were from travellers from Lebanon detected by other countries. Additional genome sequencing is thus needed to allow surveillance of variants in circulation. MethodsNine hundred and five SARS-CoV-2 genomes were sequenced using the ARTIC protocol. The genomes were derived from SARS-CoV-2-positive samples, selected retrospectively from the sentinel COVID-19 surveillance network, to capture diversity of location, sampling time, gender, nationality and age. ResultsAlthough sixteen PANGO lineages were circulating in Lebanon in January 2021, by February there were just four, with the Alpha variant accounting for 97% of samples. In the following two months, all samples contained the Alpha variant. However, this had changed dramatically by June and July, when all samples belonged to the Delta variant. DiscussionThis study provides a ten-fold increase in the number of SARS-CoV-2 genomes available from Lebanon. The Alpha variant, first detected in the UK, rapidly swept through Lebanon, causing the countrys largest wave to date, which peaked in January 2021. The Alpha variant was introduced to Lebanon multiple times despite travel restrictions, but the source of these introductions remains uncertain. The Delta variant was detected in Gambia in travellers from Lebanon in mid-May, suggesting community transmission in Lebanon several weeks before this variant was detected in the country. Prospective sequencing in June/July 2021 showed that the Delta variant had completely replaced the Alpha variant in under six weeks.