Essential Oil of Thymus munbyanus subsp. coloratus from Algeria: Chemotypification and in vitro Biological Activities

Thymus munbyanus subsp. coloratus (Lamiaceae) is a small shrub endemic to Algeria and Morocco where is found in lawns, rockeries and mountainous regions. From a phytochemical point of view this taxon has never been characterized. In this work we have analysed the chemical compositions of the essential oils obtained from inflorescences and vegetative parts by GC/MS. A new chemotype, i.e. borneol‐chemotype, was characterized for the first time in the species. Furthermore, we assessed the biological activities of essential oils, namely the antioxidant, antimicrobial and cytotoxicity on tumor cells that were evaluated by the DPPH, ABTS, and FRAP, disc diffusion, and MTT methods, respectively. Biological assays highlighted a moderate inhibitory effect on Staphylococcus aureus, Escherichia coli and Candida albicans (inhibition zone diameter in the range 9 – 10 mm), and noteworthy cytotoxicity on A375 human melanoma cells (IC₅₀ of 46.95 μg/ml).     

Plasmids impact on rhizobia-legumes symbiosis in diverse environments

Rhizobia are a well-known group of soil bacteria that establish symbiotic relationship with leguminous plants, fix atmospheric nitrogen, and improve soil fertility. To fulfill multiple duties in soil, rhizobia are elaborated with a large and complex multipartite genome composed of several replicons. The genetic material is divided among various replicons, in a way to cope with, and satisfy the diverse functions of rhizobia. In addition to the main chromosome, which is carrying the essential (core) genes required for sustaining cell life, the rhizobia genomes contain several extra-chromosomal plasmids, carrying the nonessential (accessory) genes. Occasionally, some mega-plasmids, denoted as secondary chromosomes or chromids, carry some essential (core) genes. Furthermore, specific accessory gene sequences (the symbiotic chromosomal islands) are incorporated in the main chromosome of some rhizobia species in Bradyrhizobium and Mesorhizobium genera. Plasmids in rhizobia are of variable sizes. All of the plasmids in a Rhizobium cell constitute about 30–50% of the genome. Rhizobia plasmids have specific characters such as miscellaneous genes, independent replication system, self-transmissibility, and instability. The plasmids regulate several cellular metabolic functions and enable the host rhizobia to survive in diverse habitats and even under stress conditions. Symbiotic plasmids in rhizobia are receiving increased attention because of their significance in the symbiotic nitrogen fixation process. They carry the symbiotic (nod, nif and fix) genes, and some non-symbiotic genes. Symbiotic plasmids are conjugally-transferred by the aid of the non-symbiotic, self-transmissible plasmids, and hence, brings about major changes in the symbiotic interactions and host specificity of rhizobia. Besides, the rhizobia cells harbor one or more accessory, non-symbiotic plasmids, carrying genes regulating various metabolic functions, rhizosphere colonization, and nodulation competitiveness. The entire rhizobia-plasmid pool interacting in harmony and provides rhizobia with substantial abilities to fulfill their complex symbiotic and non-symbiotic functions in variable environments. The above concepts are extensively reviewed and fairly discussed.     

Endothelins and their receptors in embryo implantation

As a critical stage of pregnancy, the implantation of blastocysts into the endometrium is a progressive, excessively regulated local tissue remodeling step involving a complex sequence of genetic and cellular interplay executed within an optimal time frame. For better understanding the causes of infertility and, more importantly, for developing powerful strategies for successful implantations and combating infertility, an increasing number of recent studies have been focused on the identification and study of newly described substances in the reproductive tree. The endothelins (ET), a 21-aminoacidic family of genes, have been reported to be responsible for the contraction of vascular and nonvascular smooth muscles, including the smooth muscles of the uterus. Therefore, this review aims to comprehensively discuss the physiological role of endothelins and signaling through their receptors, as well as their probable involvement in the implantation process.     

An Inverse Finite Element Method for Determining the Tissue Compressibility of Human Left Ventricular Wall during the Cardiac Cycle

The determination of the myocardium’s tissue properties is important in constructing functional finite element (FE) models of the human heart. To obtain accurate properties especially for functional modeling of a heart, tissue properties have to be determined in vivo. At present, there are only few in vivo methods that can be applied to characterize the internal myocardium tissue mechanics. This work introduced and evaluated an FE inverse method to determine the myocardial tissue compressibility. Specifically, it combined an inverse FE method with the experimentally-measured left ventricular (LV) internal cavity pressure and volume versus time curves. Results indicated that the FE inverse method showed good correlation between LV repolarization and the variations in the myocardium tissue bulk modulus K (K = 1/compressibility), as well as provided an ability to describe in vivo human myocardium material behavior. The myocardium bulk modulus can be effectively used as a diagnostic tool of the heart ejection fraction. The model developed is proved to be robust and efficient. It offers a new perspective and means to the study of living-myocardium tissue properties, as it shows the variation of the bulk modulus throughout the cardiac cycle.     

Development of Pegylated Nano-Phytosome Formulation with Oleuropein and Rutin to Compare Anti-Colonic Cancer Activity with Olea Europaea Leaves Extract

Olive leaf extract is a valuable source of phenolic compounds; primarily, oleuropein (major component) and rutin. This natural olive leaf extract has potential use as a therapeutic agent for cancer treatment. However, its clinical application is hindered by poor pharmacokinetics and low stability. To overcome these limitations, this study aimed to enhance the anticancer activity and stability of oleuropein and rutin by loading them into PEGylated Nano-phytosomes. The developed PEGylated Nano-phytosomes exhibited favorable characteristics in terms of size, charge, and stability. Notably, the anticolonic cancer activity of the Pegylated Nano-phytosomes loaded with oleuropein (IC50=0.14 μM) and rutin (IC50=0.44 μM) surpassed that of pure oleuropein and rutin alone. This outcome highlights the advantageous impact of Nano-phytosomes to augment the anticancer potential of oleuropein and rutin. These results present a promising pathway for the future development of oleuropein and rutin Nano-phytosomes as effective options for passive tumor-targeted therapy, given their improved stability and efficacy.     

Gene expression in Mercurialis annun flowers: In vitro translation and sex genotype specificity. Male-specific cDNA cloning and hormonal dependence of a corresponding specific RNA

Summary Sequences specifically expressed in flowers of each sex type of Mercurialis annua have been demonstrated by a comparative analysis of the translation products of their poly(A)⁺ RNA populations (wheat germ system, two-dimensional electrophoresis). This method confirms previous results of hybridization kinetics: the staminate flowers of the normal fertile male (wild type) and restored fertile male strain (identical morphology) and those of the sterile male genotype contain specific poly(A)⁺ RNAs and sequences shared by sets of two of these males, as well as numerous common sequences. The pistillate flowers of the constructed female strain 19_–5 (carrying male sterility determinants) also contains specific poly(A)⁺ RNA compared to identical flowers of a normal female genotype. In vitro translation, however, showed a specificity (not revealed by hybridization kinetics) in the normal female genotype compared to a normal male genotype and to the female strain 19_–2 (female strain cDNAs hybridized 100% to poly(A)⁺ RNAs of male and female 19_–5 genotypes). Cloning certain specific sequences (cDNAs) of the fertile male wild type and using one cDNA as probe also confirms the previously described male specificity. Moreover, the hormonal dependence of RNA corresponding to a specific male probe is demonstrated: its kinetics of disappearance are a function of the action of the feminizing hormone (cytokinins). These results are in agreement with our hypothesis of sexual organogenesis: sexual hormones controlled by regulator genes of the sexual genotype induce, in definite cell lineages of bipotential meristems, the expression of genes specific for male or female expression.     

Oleuropein, a non-toxic olive iridoid, is an anti-tumor agent and cytoskeleton disruptor

Oleuropein, a non-toxic secoiridoid derived from the olive tree, is a powerful antioxidant and anti-angiogenic agent. Here, we show it to be a potent anti-cancer compound, directly disrupting actin filaments in cells and in a cell-free assay. Oleuropein inhibited the proliferation and migration of advanced-grade tumor cell lines in a dose-responsive manner. In a novel tube-disruption assay, Oleuropein irreversibly rounded cancer cells, preventing their replication, motility, and invasiveness; these effects were reversible in normal cells. When administered orally to mice that developed spontaneous tumors, Oleuropein completely regressed tumors in 9-12 days. When tumors were resected prior to complete regression, they lacked cohesiveness and had a crumbly consistency. No viable cells could be recovered from these tumors. These observations elevate Oleuropein from a non-toxic antioxidant into a potent anti-tumor agent with direct effects against tumor cells. Our data may also explain the cancer-protective effects of the olive-rich Mediterranean diet.     

Changes in serum cytokine levels in active tuberculosis with treatment

It has been reported that IFN-gamma, TNF-alpha, and IL-12 stimulate, and that IL-10, TGF-beta, and IL-4 suppress the protective immune response against tuberculosis. We aim to evaluate changes in the serum levels of pro and antiinflammatory cytokines in active pulmonary tuberculosis (APTB) and the possible effects of treatment on these changes. Serum IL-12p40, IL-4, IL-10, TNF-alpha, IFN-gamma, and TGF-beta1 levels were determined in 20 APTB cases (group 1) before and 2, 4, and 6 months after therapy. The same parameters were also determined in 9 inactive pulmonary tuberculosis (IPTB) cases (group 2) and 9 healthy controls (HC, group 3). Before treatment, the mean serum IFN-gamma, TNF-alpha, and IL-10 levels in group 1 were statistically higher than those in group 2 (P=.001, P=.024, P=.016, resp) or group 3 (P=.003, P=.002, P=.011, resp). The levels in group 1 decreased significantly after treatment (P=.001 for IFN-gamma, P=.004 for TNF-alpha, P=.000 for IL-10). The serum levels of IL-12p40 were significantly higher in group 1 than in group 3 (P=.012) and decreased insignificantly after treatment. There was no difference in serum IL-4 and TGF-beta1 levels among the groups (P>.05). Because the serum IL-12p40, IL-10, TNF-alpha, and IFN-gamma levels were high in APTB, we believe that these cytokines have important roles in the immune response to Mycobacterium tuberculosis (M tuberculosis). These parameters could be used in follow-up as indicators of the success of APTB therapy.     

Parasitoids of chickpea leafminer Liriomyza cicerina (Diptera: Agromyzidae) and their parasitism rate on chickpea fields in North Tunisia

In recent years, as a consequence of climatic changes, the leafminer Liriomyza cicerina had emerged as a serious pest in chickpea crops causing considerable damage in Tunisia. Thus, the search of control methods is necessary. The aim of this research was to monitor and identify the naturally occurring parasitoids of the chickpea leafminer Liriomyza cicerina in insecticide-free chickpea-growing areas located in North-Western Tunisia. Chickpea leaves with mines were weekly sampled from Beja and Kef sites during 2016 and 2017 and kept to observe and count emerging leafminer and parasitoid adults in the laboratory. Results revealed that L. cicerina parasitoids complex species included three hymenopteran parasitoids namely Opius monilicornis (Fisher, 1962) (Braconidae); Diglyphus isaea (Walker, 1838) (Eulophidae) and Diaulinopsis arenaria (Erdös, 1951) (Eulophidae). These parasitoids were identified and recorded for the first time in Tunisia on L. cicerina with parasitism rate varied between 13% and 52.5%. The most common species was O. monilicornis. The correlation between infestation rate on chickpea plants and number of emerged three parasitoids was calculated revealing high significant and positive correlations. The diversity index (H′) was also calculated. The three parasitoids were found in two sites Beja and Kef; while the diversity differed during the developmental stage of chickpea crops.