Large-scale preparation of clove essential oil and eugenol-loaded liposomes using a membrane contactor and a pilot plant.

Based on our previous study where optimal conditions were defined to encapsulate clove essential oil (CEO) into liposomes at laboratory scale, we scaled-up the preparation of CEO and eugenol (Eug)-loaded liposomes using a membrane contactor (600 mL) and a pilot plant (3 L) based on the principle of ethanol injection method, both equipped with a Shirasu Porous Glass membrane for injection of the organic phase into the aqueous phase. Homogenous, stable, nanometric-sized and multilamellar liposomes with high phospholipid, Eug loading rates and encapsulation efficiency of CEO components were obtained. Saturation of phospholipids and drug concentration in the organic phase may control the liposome stability.

Comparison between ultrafine and fine particulate matter collected in Lebanon: Chemical characterization, in vitro cytotoxic effects and metabolizing enzymes gene expression in human bronchial epithelial cells.

During the last few years, the induction of toxicological mechanisms by atmospheric ultrafine particles (UFP) has become one of the most studied topics in toxicology and a subject of huge debates. Fine particles (FP) and UFP collected at urban and rural sites in Lebanon were studied for their chemical composition and toxicological effects. UFP were found more enriched in trace elements, secondary inorganic ions, total carbon and organic compounds than FP.

Liposomes incorporating cyclodextrin-drug inclusion complexes: Current state of knowledge.

Cyclodextrins (CDs) are cyclic oligosaccharides, consisting of glucopyranose units, which are able to form host-guest inclusion complexes with lipophilic molecules. The ability of CD to increase drug solubility may be used to increase drug entrapment in the aqueous compartment of liposomes and liposomes can protect CD/drug inclusion complexes until drug release. Liposomes are phospholipid vesicles composed of lipid bilayers enclosing one or more aqueous compartments.

Effect of Progesterone, Its Hydroxylated and Methylated Derivatives, and Dydrogesterone on Lipid Bilayer Membranes.

The interaction of progesterone (PG), 17-hydroxyprogesterone (17-OHPG), 21-hydroxyprogesterone (21-OHPG), medroxyprogesterone (MP), medroxyprogesterone acetate (MPA), and dydrogesterone (DYG), with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposome, was investigated as a function of drug concentration using Fourier transform infrared spectroscopy and differential scanning calorimetry. The results reveal that progesterone and its derivatives changed the physical properties of the DPPC bilayers by decreasing the main phase-transition temperature (T m) and enthalpy (ΔH m), abolishing the pre-transition and disordering the membrane. From the thermodynamic parameters analysis, we concluded that PG, 21-OHPG, and MPA are localized inside the membrane.

Preparation and characterization of clove essential oil-loaded liposomes.

In this study, suitable formulations of natural soybean phospholipid vesicles were developed to improve the stability of clove essential oil and its main component, eugenol. Using an ethanol injection method, saturated (Phospholipon 80H, Phospholipon 90H) and unsaturated soybean (Lipoid S100) phospholipids, in combination with cholesterol, were used to prepare liposomes at various eugenol and clove essential oil concentrations. Liposomal batches were characterized and compared for their size, polydispersity index, Zeta potential, loading rate, encapsulation efficiency and morphology.

Antibacterial and antibiofilm activities of polysaccharides, essential oil, and fatty oil extracted from Laurus nobilis growing in Lebanon.

Objective: To evaluate the antibacterial activity of the extracts of Laurus nobilis against three Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212 and Staphylococcus epidermidis CIP 444) and two Gram-negative bacteria (Escherichia coli ATCC 35218 and Pseudomonas aeruginosa ATCC 27853). Also, the antibiofilm activity has been investigated against the biofilm produced by Staphylococcus epidermidis CIP 444.

Materials: The polysaccharides, essential oil, and fatty oils extracted from the plant were used in broth microdilution methods to study the minimal inhibitory concentration, and then the minimal bactericidal concentration was determined.

Waterpipe effects on pulmonary function and cardiovascular indices: a comparison to cigarette smoking in real life situation.

Introduction: Smoking is known to have physiological effects on biological systems. The purpose of this study is to evaluate acute and chronic effects on pulmonary functions and cardiovascular indices of waterpipe (WP) smoking in real life circumstances.

Methods: Three groups were included in the study: non-smokers (N = 42), WP smokers (N = 42) and cigarette smokers (N = 48).

Morphological and physicochemical characterization of liposomes loading cucurbitacin E, an anti-proliferative natural tetracyclic triterpene.

Cucurbitacin E (Cuc E), an oxygenated triterpene molecule, has demonstrated anti-proliferative effect on various cancer cells. Here, we examined the effect of Cuc E on the membrane morphology and properties using differential scanning calorimetry, transmission electron microscopy and atomic force microscopy techniques. Dipalmitoylphosphatidylcholine vesicles were prepared by the thin film hydration method in the absence and presence of Cuc E at molar ratios 100:12 and 100:20.

Traffic-related air pollution. A pilot exposure assessment in Beirut, Lebanon.

Traffic-related volatile organic compounds (VOCs) pollution has frequently been demonstrated to be a serious problem in the developing countries. Benzene and 1,3-butadiene (BD) have been classified as a human carcinogen based on evidence for an increased genotoxic and epigenotoxic effects in both occupational exposure assessment and in vivo/in vitro studies. We have undertaken a biomonitoring of 25 traffic policemen and 23 office policemen in Beirut, through personal air monitoring, assessed by diffusive samplers, as well as through the use of biomarkers of exposure to benzene and BD.

Essential oils encapsulated in liposomes: a review.

In the recent years there has been an increased interest toward the biological activities of essential oils. However, essential oils are unstable and susceptible to degradation in the presence of oxygen, light and temperature. So, attempts have been made to preserve them through encapsulation in various colloidal systems such as microcapsules, microspheres, nanoemulsions and liposomes.

Preparation and characterization of liposomes incorporating cucurbitacin E, a natural cytotoxic triterpene.

Cucurbitacin E (Cuc E), highly oxygenated triterpene from cucurbitaceae family, was demonstrated to possess anti-proliferative, anti-inflammatory and anti-oxidant activities. Here, we studied the effect of Cuc E on the properties of the phospholipid membrane. Large unilamellar vesicles, with and without sulforhodamine B (SRB), were prepared in the absence and presence of Cuc E.

Extraction of infrequent simple motifs from a finite set of sequences using a lattice structure.

In this paper we present a method for finding infrequent simple motifs in a finite set of sequences. The method uses a lattice structure and minimal forbidden patterns. It is based on a method for solving the Simple Motif Problem and has the potential to discover new patents in biological macromolecules.

p-Hydroxybenzoate esters metabolism in MCF7 breast cancer cells.

Parabens are among the most frequently used preservatives to inhibit microbial growth and extend the shelf life of a range of consumer products. The objective of the present study was to gain insight into the metabolism of parabens in breast cancer cells (MCF7) since they have demonstrated estrogenic activity towards these cells and have been detected in breast cancer tissues. The toxicity of parabens to MCF7 cells was determined using MTT assays.

A biclustering algorithm based on a bicluster enumeration tree: application to DNA microarray data.

Background: In a number of domains, like in DNA microarray data analysis, we need to cluster simultaneously rows (genes) and columns (conditions) of a data matrix to identify groups of rows coherent with groups of columns. This kind of clustering is called biclustering. Biclustering algorithms are extensively used in DNA microarray data analysis.

Phospholipase A2 subclasses in acute respiratory distress syndrome.

Phospholipases A2 (PLA2) catalyse the cleavage of fatty acids esterified at the sn-2 position of glycerophospholipids. In acute lung injury-acute respiratory distress syndrome (ALI-ARDS) several distinct isoenzymes appear in lung cells and fluid. Some are capable to trigger molecular events leading to enhanced inflammation and lung damage and others have a role in lung surfactant recycling preserving lung function: Secreted forms (groups sPLA2-IIA, -V, -X) can directly hydrolyze surfactant phospholipids.