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International audience; Bacillus thuringiensis is a microorganism used for the production of biopesticides worldwide. In the present paper, different kinetic models were analyzed to study and compare three different strains of Bt ssp kurstaki (LIP, BLB1, and HD1). Bioperformances (vegetative cell, spore, substrate, and protein) and successive culture phases (oxidative growth, limitation and sporulation, and protein release) were depicted with an overarching aim to estimate total protein productivity, yield, and titer. In the end, two models were calibrated using experimental dataset (11 batches culture in 3 L bioreactor with semisynthetic medium), subsequently validated, and statistically compared. Both models satisfactorily followed the dynamics of the experimental data. Finally, a dynamic model was selected following the Akaike information criterion (AIC).

This investigation presents laboratory and field deployment results that demonstrate the potential candidacy utilizing Nano and bio-technologies to create superior chemicals for novel applications to increase oil recovery from both onshore and offshore reservoirs. Nano-technology is gaining momentum as a tool to improve performance in multiple industries, and has shown significant potential to enhance hydrocarbon production. The laboratory analysis and specifically designed coreflood results indicate there are beneficial interactions at liquid-nano solid interface that increase oil mobility. This will increase the surface activity of chemical surfactants and thereby make them the dominant agents to mobilize and recover oil from oil-bearing reservoirs. Advances in biotechnology offer another rich resource of knowledge for surface active materials that are renewable and more environmental-friendly. In addition, our studies also demonstrate that bio-surfactants are well-suited to provide superior performances in enhancing oil recovery. Nano-particles and biosurfactants may be included with synthetic surfactants to create novel and more efficient surface active agents for enhanced oil recovery. These formulations can promote better flow back of the injected stimulation fluids and additional mobilization to extract more oil from the matrix and micro-fractures. Laboratory experiments demonstrate that the specialized surfactant formulations created, interact with mixed or oil-wet low permeability formations to produce additional oil. Furthermore, this investigation also compares the total production on a candidate field with respect to typical water flood and the novel formulated surfactant approach. For each surfactant treatment, the overall designed injected fluid volume is 1500 m3 (~ 396,000 gallons) with 4 gpt (gallon per thousand unit) of surfactant concentration. Results indicate improved oil production with longer exposure time of the key surfactants within the reservoir. Enhanced surface wetting and super-low interfacial tension (IFT) at lower chemical concentrations are recognized to be the main mechanisms. The novel surfactant also shows stronger sustainability and endurance in keeping rock surface wettability over traditional surfactant system up to 5 times for an 8 PV wash. Furthermore, this can assist to identify and initiate the optimization of the identified mechanisms for potential applications within other compatible reservoirs. A number of successful field applications of EOR with special formulated nano and bio-based surfactant formulation are discussed in this paper. This unique study bridges the gap between the field realized results and lab optimization to enhance feasibility as a function of time and cost.

The essential oils of fifteen Eucalyptus species harvested from the Jbel Abderrahman and Korbous arboreta (North East Tunisia) were screened for their antibacterial activities by the agar disc diffusion method. The activity of the Eucalyptus essential oils varied significantly within species and within strains. Eighteen major components as identified by GC/FID and GC/MS were selected for a study of the chemical and biological activity variability. The main one was 1,8-cineole, followed by spathulenol, trans-pinocarveol, ?-pinene, p-cymene, globulol, cryptone, ?-phellandrene, viridiflorol, borneol, limonene and isospathulenol. The chemical principal component analysis identified five species groups and subgroups, where each group constituted a chemotype, however that of the values of zone diameter of the inhibition (zdi) identified six groups of Eucalyptus oils, characterized by their antibacterial inhibition ability. The strongest activity was shown by E. platypus oil against Enterococcus faecalis and by E. lamannii oil against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. A correlation between the levels of some major components and the antibacterial activities was observed.

In order to improve photovoltaic efficiency, researches have been carried out on silicon nanowires (SiNWs). In this article, we report a comparative study between silicon substrate (Si) and SiNWs developed by a metal-assisted chemical etching (Ag) method at different etching times (25, 10 and 5 min). Scanning electron microscopy (SEM), transmission electron microscopy and X-ray diffraction were used to collect the morphological and structural information on the SiNWs. Raman spectroscopy shows that the intensity of the nanowires is 4 to 10 times higher than that of the substrate, and increases with increase in etching time. The total reflectance of SiNWs reduced to less than 5% over the entire visible range. The low reflectance and zero transmittance of SiNWs lead to higher absorbance in the visible wavelength range. The SiNW-etched nanowire structure (25 min) works best for capturing light, we believe that having longer nanowires improves the optical working of the nanostructures and may be a potential candidate for high efficiency photovoltaic solar cells and other optic devices.

In this work, the structures, quantum chemical descriptors, morphologic characterization of the azomethoxy-calix[4]arene were investigated. The analyses and interpretation of the theoretical and the experimental IR spectroscopy results for the corresponding compounds was performed. The complexation of the azo-methoxy-calix[4]arene with Zn2+, Hg2+, Cu2+, Co2+, Ni2+, Pb2+ and Cd2+ metal cations has been calculated by the dispersion corrected density functional theory (DFT-D3). The values of the interaction energies show that the specific molecule is more selective to the Cu2+ cation. The study of the reactivity parameters confirms that the azo-methoxy-calix[4]arene molecule is more reactive and sensitive to the Cu2+ cation than that Co2+ and Cd2+. In addition, the investigation of the electrophilic and nucleophilic sites has been studied by the molecular electrostatic potential (MEP) analysis. The Hirshfeld surface (HS) analysis of the azo-methoxy-calix[4]arene-Cu2+ interaction have been used to understand the Cu...hydrogen-bond donors formed between the cation and the specific compound. The Quantum Theory of Atoms in Molecules (QTAIM) via Non covalent Interaction (NCI) analysis was carried out to demonstrate the nature, the type and the strength of the interaction formed between the Cu2+ cation and the two symmetrical ligands and the cavity. Finally, the chemical sensor properties based on the Si/SiO2/Si3N4/Azo-methoxy-calix[4]arene for detection of Cu2+ cation were studied. Sensing performances are determined with a linear range from 10(-5.2) to 10(-2.2) M. The Si/SiO2/Si3N4/azo-methoxy-calix[4]arene structure is a promoter to have a good performance sensor. (C) 2021 Elsevier B.V. All rights reserved. Tunisian's Ministry of high education and scientific research The authors acknowledge financial support from the Tunisian's Ministry of high education and scientific research. We thanks to, M.E.C. and F.J.M. Laboratorio Nacional de Supercomputodel Sureste de Mexico (LNS-BUAP) of the CONACyT network of national labora-tories for the computer resources and support provided. We thank to, Dr. Arzu Karayel and Dr. Sevil ozknal for the theoretical calcu-lations of the azo-methoxy-calix [4] arene-cations complexes. WOS:000701648800003 2-s2.0-85111808860 PubMed: 34358783

Reservoir characterization and quantification of initial oil in place in carbonate reservoirs are challenging steps, where reliability of the produced data and its uncertainty level will be critical for reservoir development. The field, under study, is a complex carbonate reservoir, with variations in its fluid contacts and stratigraphic settings. This carbonate reservoir requires an integrated petrophysical evaluation study that involves geology, geophysics, openhole logs, special core analysis (SCAL), reservoir rock typing (RRT), saturation height model (SHM) and detailed reservoir/fluid analysis, that would result in reliable reservoir characterization, fluid contacts, and fluids in place estimation with least levels of uncertainty. An innovative integrated petrophysical evaluation has been conducted for reservoir characterization. Using core data, reservoir quality index (RQI) bins have been imposed over porosity-permeability cross-plots to define the reservoir rock types, RRTs, in this carbonate reservoir. An advanced permeability log has been developed from porosity, clay/bound water, pore size, core, diagenetic and mobility data, have derived for each rock type. The Saturation Height Model (SHM) was based on SCAL data of Mercury Injection Capillary Pressure (MICP), capillary pressures-water saturation from Porous plate/Centrifuge and Relative Permeability for every RRT for reservoir subunits. The free water level (FWL) derived from formation pressure has been used to identify an initial oil water contact, and thus it has provided good comparison of SW_Log & SW_SHM for reservoir modeling. An initial water saturation, relative permeability and residual oil saturation from SCAL data have been used in evaluation. The log data of water saturation from resistivity, core saturation height model and reservoir pressure depletion in production wells have been evaluated for an improving reservoir characterization. The advanced and integrated evaluation approach of subsurface and well test data has been used to provide reliable carbonate reservoir properties and results on porosity, permeability, fluid contacts, reservoir rock typing, initial water saturation, and initial oil in place. It has provided reliable reservoir characterization, reservoir modeling approach for this complex carbonate reservoir. Hence, this approach has provided reliable assurance and important benefits for reservoir characterization, optimization and reservoir management. The integrated petrophysical approach of this paper presents an integrated reservoir petrophysical approach for carbonate reservoirs. It is an integrated approach that used the available log, core, dynamic pressure data, to derive reservoir rock types, assignment of permeability as a function of porosity, pore size, clay/bound water, diagenetic and mobility data. Integration of available petrophysical, pressure, and SCAL data to derive the reservoir fluid contacts, and develop SHMs for oil in place estimation and reservoir modeling purposes.

Introduction: Risk of venous thromboembolism (VTE) in lung cancer patients substantially increases with the addition of chemotherapy. Platinum-based regimens claim to be associated with a very high VTE rate. Objectives: Determine the prevalence and characteristics of VTE in adult patients receiving platinum-based chemotherapy and analyze the importance of the patients’ tumor and treatment characteristics in predicting the occurrence of VTE. Patients and Methods: Patients who had received platinum based chemotherapy for lung cancer between January 2016 and December 2018 were retrospectively identified. Patients were followed for development of VTE throughout the entire duration of therapy and one month thereafter. Results: Eighteen patients (88.8% males, median age: 62 years) treated with platinum-based regimens (49 cisplatin, 31 carboplatin) were included. VTE were reported in 15 patients (18.8%). Thrombosis included deep vein thrombosis (DVT) in 8 (10%), pulmonary embolism (PE) in 6 (7,5%) and DVT with PE in 1 (1,25%). Most patients (70%) had stage IV cancer and only 5% had stage I or II. In the multivariate analysis, the occurrence of TVE were not associated statistically with advanced-stage disease, gender, age, and different risk scores. Carboplatin-Etoposide was associated with a higher risk of VTE (p=0.049) in univariate analysis. In multivariate analysis, Carboplatin-Etoposide (p=0,045) and carboplatin-Navelbine (p=0.048) increased the risk of VTE. Conclusion: A high incidence of VTE in patients receiving platinum based chemotherapy was demonstrated in this study. Prospective studies are crucial to highlight the necessity of thromboprophylaxis in patients receiving platinum based chemotherapy.

This study focuses on the morphological, electrical and dielectric properties of chromogenic calix[4]arene amide combined with Single-Walled Carbon Nanotubes (SWCNTs). The effects of SWCNTs addition on the performance of the formed nanocomposite material were studied. After the dispersion process, the spin-coated nanocomposite thin films were prepared over indium tin oxide-coated glass substrates. Using scanning electron microscopy, morphological features and surface roughness were examined before and after SWCNTs loading on the chromogenic calix[4]arene amide. In addition, the charge carrier transport properties and conduction mechanism of the chromogenic calix[4]arene amide/SWCNT thin films have been studied by using current–voltage (I–V) characteristics and dielectric spectroscopy technique. The experimental results have shown a significantly enhancement of conductivity and dielectric properties of the nanocomposite thin film with increasing SWCNTs reinforcement. Experimental results were theoretically fitted corresponding to an equivalent circuit aiming to reveal dielectric parameters of the nanocomposite devices. Finally, these prepared nanocomposite films have potential applications in nanoelectronic and sensing devices.

This paper presents an in-depth analysis of the I (V) and I(V-T) characteristics of the Schottky Pt / ZnO nanowire diode. Detailed analyzes were performed to extract the various electrical parameters and information on the interface states. The characteristic parameters of the structure such as barrier height, ideality factor, saturation current and series resistance were determined from the current-voltage measurement. The ideality factor (3.58) value at room temperature is higher than unity probably due to the presence of the n-ZnO / p-Si heterojunction in series with the Pt / ZnO nanowire. The value of the computed barrier height of the diode (0.65 eV) using the thermionic emission model is in good agreement with the theoretically predicted value. Indeed, these two values obtained by the current-voltage I(V) characteristics suggested the presence of interface states between the Pt and the nanowire ZnO. To confirm this observation, we carried out the measurement C (V).

International audience; Aims: Oxidative stress and inflammation play a pathogenic role in atherosclerosis. Thioredoxin-1 (Trx-1) is an anti-oxidative, anti-inflammatory protein with atheroprotective effects. However, in vivo cleavage of Trx-1 generates a truncated pro-inflammatory protein, Trx-80, which compromises the therapeutic use of Trx-1. Here we analysed whether the thioredoxin-mimetic peptide (TxMP), CB3 might exert anti-oxidative, anti-inflammatory, and atheroprotective effects in ApoE2.Ki mice.Methods and results: We synthesized a small TxMP, Ac-Cys-Pro-Cys-amide, CB3 and characterized its antioxidant and anti-inflammatory effects on cultured peritoneal murine macrophages. CB3 significantly and dose-dependently reduced the level of reactive oxygen species in lipopolysaccharides (LPS)-activated macrophages. In addition, it efficiently lowered LPS-induced inflammatory process through NF-κB inhibition, as evidenced by the reduced secretion of monocyte chemoattractant protein-1, interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α by macrophages. Nevertheless, CB3 did not affect cholesterol accumulation in macrophages. A daily-administered dose of 10 µg/g body weight CB3 to ApoE2.Ki mice on high fat diet did not affect plasma of total cholesterol and triglycerides levels but significantly reduced the plasma levels of pro-inflammatory cytokines (IL-33 and TNF-α) and oxidative markers. In contrast, it significantly induced the plasma levels of anti-inflammatory proteins (adiponectin, IL-10). In addition, CB3 reduced the number of pro-inflammatory M1 macrophages in spleen and decreased the ratio of M1/M2 macrophages in atherosclerotic lesion areas. Finally, CB3 significantly reduced the surface area of aortic lesions.Conclusions: Our results clearly showed that similar to the full length Trx-1, CB3 exerts protective effects, by reducing inflammation and oxidative stress in macrophages and in ApoE2.Ki mice. The atheroprotective effect of CB3 opens promising therapeutic approaches for treatment of atherosclerosis.

We report a novel sensitive and selective optical sensor based on [Eu (dmso)8] [Eu (η2NO3)2(dmso)4(α-Mo8O26)0.5] [Mo6O19] (1) for sulfaguanidine (Sg) determination in environmental water. The complex formation processes between Sg and 1 were studied spectrophotometrically, showing that the stoichiometric ratio was determined as 1:1. The sensing thin film was constructed by spin coating of 1 onto glass plate surface. The proposed membrane shows a significant absorbance signal change on exposure to buffer solution of pH 7 containing Sg. The optode surface topology reveals agglomerations after the Sg detection process proving Sg recognition by the thin film. It displays a calibration response for Sg over a wide concentration range of 10−11 M to 10−5 M with a detection limit (LOD) of 6.3 × 10−13 M and response time of 8 min. This optode exhibits good selectivity toward sulfaguanidine (Sg) in comparison with sulfamethoxazole (SMX), Cloxacillin (Clox), l -cystine (L-cys), tryptophan (tryp), NO3−, and Cl−. The proposed absorbance sensor in this work was found to be stable, has good repeatability, reproducibility and an accepted lifetime. Finally, this optode has been applied for Sg determination in mineral and tap water sample finding encouraged results.

Ethnopharmacological evidence Thymus atlanticus (TA) is used in traditional medicine in Morocco to treat chronic inflammatory diseases, after local and oral treatment. Aim of study This study aimed to investigate the in vitro and in vivo anti-inflammatory and anticoagulant activities of an aqueous extract (AE) and polyphenol fraction (PF) derived from TA. Materials and methods The effect of AE and PF on monocyte chemoattractant protein-1 (MCP-1) production by naive and LPS-stimulated peritoneal macrophages isolated from C57Bl/6 mice was assessed by ELISA assay. The effect of chronic administration of the extracts at three different doses by oral rout for 2 weeks on blood coagulation and inflammation induced by carrageenan in Wistar rats was evaluated. In addition, the in vitro anticoagulant effect was tested on blood plasma collected from healthy rats using the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) tests. The acute toxicity of AE was investigated. Phytochemical analysis was carried out by HPLC. Results Analysis by HPLC indicated rosmarinic acid as the main phenolic acid in TA extracts. Compared to control macrophages, MCP-1 level was lower in medium supplemented with AE at 50 and 500 μg/mL and PF at 500 μg/mL, but higher in medium with PF at 50 μg/mL. Rosmarinic and chicoric acids, served as controls, significantly decreased MCP-1 production. Chronic oral administration of TA extracts prevented inflammation induced by carrageenan and induced a significant prolongation of blood coagulation time, in a dose dependant manner, in Wistar rats. The results of the in vitro assay showed that the coagulation time was significantly prolonged in plasma incubated with extracts in APTT, PT and TT tests. Lethal dose 50 of AE in mice was 27.90 ± 1.19 g/kg. Conclusion This study indicated TA as an herb with anti-inflammatory and anticoagulant proprieties and supports the traditional use of this plant for the treatment of inflammatory diseases.

Experimental tests have been carried out on the sediments in order to obtain these geotechnical and environmental properties. The sediments studied present loamy nature, high plasticity, and low swelling potential with a capacity to immobilize the organic and inorganic pollutants. The sediments studied are contaminated by the organic matter and in heavy metals. The environmental behavior proves the immobility of heavy metals in the sediments. The valuation of the sediments is possible while taking into account its nature and these plastic properties.

The urban expansion and the growth of industrial, transport and agricultural activities of Sfax agglomeration led to the change of air composition.

The aim of this study was to assess the phytotoxic potential of flowers of Citharexylum spinosum , as well as to isolate the main bioactive compounds. Results showed that the ethyl acetate extract induced the highest reduction, showing 100% inhibition of lettuce growth at 6000 ppm. This bioactive ethyl acetate extract was subjected to bio-guided chromatographic separation yielding the acetylated form of a new iridoid glucoside, designated as spinoside ( 1 ) together with two acetylated forms ( 2a ) and ( 2b ) of its known analogue durantoside-I ( 2 ). Their structures were established via their acetylated derivatives by means of spectroscopic and chemical data. The most inhibitory compound on the growth of lettuce seedling was identified to be the durantoside-I tetraacetylated ( 2b ).

Citharexylum spinosum L. (Verbenaceae) also known as Citharexylum quadrangulare Jacq. or Citharexylum fruticosum L. is an exotic tree introduced many years ago in Tunisia, specially used as a street and park ornamental tree. Essential oils (EOs) were obtained by hydrodistillation of the different parts (roots, stems, leaves, flowers and fruits; drupes) collected from trees grown in the area of Monastir (Tunisia). In total, 84 compounds, representing 90.1 - 98.4% of the whole oil composition, were identified by GC-FID and GC/MS analyses. The root EO was distinguished by its high content in monoterpene hydrocarbons (α-phellandrene; 30.8%) whereas that obtained from stems was dominated by sesquiterpene hydrocarbons (cuparene; 16.4%). The leaf oil was rich in an apocarotenoid derivative (hexahydrofarnesylacetone; 26%) and an aliphatic hydrocarbon (nonadecane; 14.5%). Flowers oil was rich in esters (2-phenylethyl benzoate; 33.5%). Finally, drupes oil was rich in oxygenated sesquiterpenes (β-eudesmol; 33.1%). Flowers oil showed a significant phytotoxic effect against lettuce seeds germination, it induces a total inhibition when tested at 1 mg/ml. Root and shoot elongation seemed to be more affected than germination. The inhibition of the shoot length varied from 3.6% to 100% and that of the root from 16.1% to 100%. The highest inhibition of 100% was detected for flower oil tested at 1 mg/ml. Our in vitro studies suggest a possible and new alternative use of C. spinosum EOs in herbicidal formulations, further experiments involving field conditions are necessary to confirm its herbicidal potential.

Ailanthus altissima Mill. Swingle (Simaroubaceae), also known as tree of heaven, is used in the Chinese traditional medicine as a bitter aromatic drug for the treatment of colds and gastric diseases. In Tunisia, Ailanthus altissima is an exotic tree, which was introduced many years ago and used particularly as a street ornamental tree. Here, the essential oils of different plant parts of this tree, viz., roots, stems, leaves, flowers, and samaras (ripe fruits), were obtained by hydrodistillation. In total, 69 compounds, representing 91.0-97.2% of the whole oil composition, were identified in these oils by GC-FID and GC/MS analyses. The root essential oil was clearly distinguishable for its high content in aldehydes (hexadecanal (1); 22.6%), while those obtained from flowers and leaves were dominated by oxygenated sesquiterpenes (74.8 and 42.1%, resp.), with caryophyllene oxide (4) as the major component (42.5 and 22.7%, resp.). The samara oil was rich in the apocarotenoid derivative hexahydrofarnesyl acetone (6; 58.0%), and the oil obtained from stems was characterized by sesquiterpene hydrocarbons (54.1%), mainly β-caryophyllene (18.9%). Principal component and hierarchical cluster analyses separated the five essential oils into four groups, each characterized by the major oil constituents. Contact tests showed that the germination of lettuce seeds was totally inhibited by all the essential oils except of the samara oil at a dose of 1 mg/ml. The flower oil also showed a significant phytotoxic effect against lettuce germination at 0.04 and 0.4 mg/ml (-55.0 ± 3.5 and -85.0 ± 0.7%, resp.). Moreover, the root and shoot elongation was even more affected by the oils than germination. The inhibitory effect of the shoot and root elongation varied from -9.8 to -100% and from -38.6 to -100%, respectively. Total inhibition of the elongation (-100%) at 1 mg/ml was detected for all the oils, with the exception of the samara oil (-74.7 and -75.1% for roots and shoots, resp.).

International audience; Intraperitoneal injection of arglabin (2.5 ng/g of body weight, twice daily, 13 weeks) into female human apolipoprotein E-2 gene knock-in (ApoE(2)Ki) mice fed a high-fat Western-type diet (HFD) reduced plasma levels of glucose and insulin by similar to 20.0% +/- 63.5% and by 50.0% +/- 2.0%, respectively, in comparison with vehicle-treated mice. Immunohistochemical analysis revealed the absence of active caspase-3 in islet sections from ApoE(2)Ki mice fed a HFD and treated with arglabin. In addition, arglabin reduced interleukin-1 beta(IL-1 beta) production in a concentration-dependent manner in Langerhans islets isolated from ApoE(2)Ki mice treated with lipopolysaccharide (LPS) and with cholesterol crystals. This inhibitory effect is specific for the inflammasome NOD-like receptor family, pyrin domain-containing 3 (NLRP3) because IL-1 beta production was abolished in Langerhans islets isolated from Nlrp3(-/-) mice. In the insulin-secreting INS-1 cells, arglabin inhibited, in a concentration-dependent manner, the maturation of pro-IL-1 beta into biologically active IL-1 beta probably through the inhibition of the maturation of procaspase-1 into active capsase-1. Moreover, arglabin reduced the susceptibility of INS-1 cells to apoptosis by increasingBcl-2 levels. Similarly, autophagy activation by rapamycin decreased apoptosis susceptibility while autophagy inhibition by 3-methyladenin treatment promoted apoptosis. Arglabin further increased the expression of the autophagic markers Bcl2-interacting protein (Beclin-1) and microtubule-associated protein 1 light chain 3 II (LC3-II) in a concentration-dependent manner. Thus, arglabin reduces NLRP3-dependent inflammation as well as apoptosis in pancreatic beta-cells in vivo and in the INS-1 cell line in vitro, whereas it increases autophagy in cultured INS-1 cells, indicating survival-promoting properties of the compound in these cells. Hence, arglabin may represent a new promising compound to treat inflammation and type 2 diabetes mellitus development.

The development of safe carriers for the use of plant extracts in industrial and health fields constitute a matter of serious concern. The development of plant derived nanoparticles may help to overcome such barriers. However, the major concern is still the safety of these carriers. The present study describes the synthesis of nanoparticles derived from Salvia officinalis L. and Ricinus communis and the evaluation of their cytotoxic and antioxidant effects. It is shown in this study that the aqueous extracts of S. officinalis L . and R. communis have the potentials to reduce silver nitrate ions to silver nanoparticles. The biosynthesized nanoparticles were analyzed by spectrophotometer and granulometric tests. The biological activities of these extracts and nanoparticles were carried out. S. officinalis L . leaf extract had the strongest antioxidant activity, followed by R. communis l eaf and fruit extracts. Altogether, the synthesized nanoparticles were safe and may serve as antioxidant products in many fields. Key words : Plant material, biosynthesis of nanoparticle, cytotoxicity, cell culture, free radicals.

Selective and sensitive optical sensor membranes (optodes) were elaborated to detect cations in aqueous solutions. The sensing films are based on chromogenic calix[4]arene derivatives. The optode membranes were studied using UV/Vis absorption spectroscopy measurements. The sensitivity of the optode has been tested for Pb 2 + , Cd 2 + , Mg 2 + and Eu 3 + ions at pH 6.8. The results showed a good selectivity response towards Eu 3 + . Low selectivity coefficients were observed for Cd 2 + and Mg 2 + where Pb 2 + can be considered as interfering ions. The characteristics of this optode such as response time, regeneration, reproducibility and lifetime are discussed.

summary Background & aims: In the present study, the polyphenol-rich extracts of four endemic medicinal plants (Thymus satureioides, Thymus zygis L., Thymus atlanticus and Thymus vulgaris) widely used in the Errachidia area (south east of Morocco) were analyzed for their hypocholesterolemic, hypotriglyceridemic, and antioxidant activities. Methods: Hyperlipidemia was induced in rats by intraperitoneal injection of Triton WR-1339 at a dose of 200 mg/kg body weight. The animals were divided into seven groups: the normolipidemic control group (NCG), the hyperlipidemic control group (HCG), the T. atlanticus-treated group (TA), the T. zygis-treated group (TZ), the T. satureioides-treated group (TS), the T. vulgaris-treated group (TV) and the Fenofibratetreated group (FF). The hyperlipidemic groups were treated with herbal extracts at a dose of 0.2 g/100 g body weight and with fenofibrate at a dose of 6.5 mg/100 g body weight. The antioxidant activity of the polyphenol-rich extracts was assessed by using the Ferric Reducing Antioxidant Power assay (FRAP), the Radical Scavenging Activity method (RSA) and the inhibition of 2,2 0-azobis (2-amidinopropane) hydrochloride (AAPH) that induces oxidative erythrocyte hemolysis. Results: After 24 h of treatment with polyphenol-rich extract from T. atlanticus, plasma total cholesterol, triglycerides and LDL-cholesterol decreased by 82.8% (P < 0.001), 96.4% (P < 0.001) and 82.2% (P < 0.001), respectively. The results demonstrate that the four aqueous thyme extracts possess antioxidant activity as evidenced by ferric reducing/antioxidant activity (equivalent to 50.79 � 2.02 mmol Trolox/g of extract) and radical scavenging activity (IC50: 0.44 � 0.02 mg/mL of extract). Conclusion: Our findings suggest that polyphenol-rich thyme extracts might be considered for therapeutic use to treat atherosclerosis.

The natural products are widely used in many fields as pharmaceutical, flavor, industrial, and additive compounds. In many cases, there is a need to evaluate the cytotoxic effect of these products and to determine the non cytotoxic concentration at which they can be used in a safe manner. The objective of the present study was to compare two methods of evaluation the cytotoxic effect of a plant extract. The MTT assay and the PI dye-inclusion assay were used to carry out the experiments. The results were then evaluated by calorimetric and flow cytometry assays. The obtained results showed that a clear difference between the two methods and the cell death using the MTT assay seem to be overestimated. To better evaluate the cytotoxic effect of natural product, we need to carry out several in vitro and in vivo tests before the judgment that a compound is safe to use and at which concentration.

The essential oils of fifteen Eucalyptus species harvested from the Jbel Abderrahman and Korbous arboreta (North East Tunisia) were screened for their antibacterial activities by the agar disc diffusion method. Eighteen major components as identified by GC/FID and GC/MS were selected for a study of the chemical and biological activity variability. The main one was 1,8-cineole, followed by spathulenol, trans-pinocarveol, α-pinene, p-cymene, globulol, cryptone, β-phellandrene, viridiflorol, borneol, limonene and isospathulenol. The chemical principal component analysis identified five species groups and subgroups, where each group constituted a chemotype, however that of the values of zone diameter of the inhibition (zdi) identified six groups of Eucalyptus oils, characterized by their antibacterial inhibition ability. The strongest activity was shown by E. platypus oil against Enterococcus faecalis and by E. lamannii oil against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. A correlation between the levels of some major components and the antibacterial activities was observed.

A studies of a tetrakis(phenylazo)calix[4]arene derivative have been developed for cation recognition. The complexation properties of this ligand towards transition metal ions have been investigated by UV–Visible and fluorescence spectroscopies. It has been found that the ligand has remarkable complexation ability for transition metal Ni 2+ , Co 2+ , Hg 2+ , heavy metal ions Al 3+ and Pb 2+ with an exceptional high affinity for the lanthanide Eu 3+ ion. The stoichiometric ratio of the complexation between the ionophore and Eu 3+ ions in acetonitrile solution has been determined by applying the molar ratio method. The complexes formed are ML 2 and ML in neutral and in basic medium respectively. The recognition properties between the thin film and the ions have also been studied. The complexation properties of the ligand with Eu 3+ ion has been confirmed by fluorescence spectroscopy.

Macrophages play a pivotal role in the pathophysiology of atherosclerosis. These cells express cathepsin L (CatL), a cysteine protease that has been implicated in atherogenesis and the associated arterial remodeling. In addition, macrophages highly express peroxisome proliferator-activated receptor (PPAR) γ, a transcription factor that regulates numerous genes important for lipid and lipoprotein metabolism, for glucose homeostasis, and inflammation. Hence, PPARγ might affect macrophage function in the context of chronic inflammation such as atherogenesis. In the present study, we examined the effect of PPARγ activation on the expression of CatL in human monocyte-derived macrophages (HMDM). Activation of PPARγ by the specific agonist GW929 concentration-dependently increased the levels of CatL mRNA and protein in HMDM. By promoter analysis, we identified a functional PPAR response element-like sequence that positively regulates CatL expression. In addition, we found that PPARγ-induced CatL promotes the degradation of Bcl2 without affecting Bax protein levels. Consistently, degradation of Bcl2 could be prevented by a specific CatL inhibitor, confirming the causative role of CatL. PPARγ-induced CatL was found to decrease autophagy through reduction of beclin 1 and LC3 protein levels. The reduction of these proteins involved in autophagic cell death was antagonized either by the CatL inhibitor or by CatL knockdown. In conclusion, our data show that PPARγ can specifically induce CatL, a proatherogenic protease, in HMDM. In turn, CatL inhibits autophagy and induces apoptosis. Thus, the proatherogenic effect of CatL could be neutralized by apoptosis, a beneficial phenomenon, at least in the early stages of atherosclerosis.

Peroxisome proliferator-activated receptor delta (PPAR-delta) is a transcription factor implicated in metabolism and inflammation. The +294T/C polymorphism in the PPAR-delta gene is associated with risk of coronary artery disease (CAD) in dyslipidemic women and hypercholesterolemic men. Whether this polymorphism influences the risk of CAD in the absence of dyslipidemia was not known, so we investigated a possible association of this polymorphism with plasma lipid and lipoprotein levels and with risk and outcome of CAD in a normolipidemic Tunisian population. Genotyping was performed by PCR-RFLP in 112 CAD patients and 113 healthy volunteers. The C-allele was significantly more frequent in patients than in controls (0.320 vs 0.189, P = 0.001). This association remained significant after adjustment for age, gender, body mass index, smoking, hypertension, and high-density lipoprotein cholesterol. Subjects carrying either one or two copies of the C-allele had a 2.7-fold higher risk of CAD than subjects homozygous for the T-allele. PPAR-delta genotypes were not associated with lipoprotein concentrations or outcome of CAD. We conclude that PPAR-delta +294T/C polymorphism is an independent risk factor of CAD in normolipidemic Tunisian subjects. The lack of association with lipoprotein concentrations suggests that the effect of the polymorphism on CAD is not mediated through lipoprotein levels in this population and that it may influence the atherosclerotic process through mechanisms involving inflammation.

Macrophage-derived reactive oxygen species contribute to the initiation and development of atherosclerosis. The cellular balance between oxidative and reductive states depends on the endogenous antioxidant capacity, with the thioredoxin-1 (Trx-1) system playing a major role. Peroxisome proliferator-activated receptor-alpha (PPARalpha) is expressed by human macrophages and exhibits anti-inflammatory properties. Here we show that the selective PPARalpha activator GW647 significantly increased the Trx-1 mRNA and protein expression in human macrophages as determined by quantitative polymerase chain reaction and Western immunoblotting. Consistently, the Trx-1 activity was significantly increased by PPARalpha activation. By contrast, PPARalpha activation led to the down-regulation of vitamin D(3) up-regulated protein 1 (VDUP-1), the physiological inhibitor of Trx-1. Analysis of the Trx-1 and VDUP-1 promoters with gene reporter assays, mutational analysis, gel shift assays and chromatin immunoprecipitation analyses revealed the presence of a functional response element specific for PPARalpha in the Trx-1 promoter and the presence of a functional activator protein 1 (AP-1) site in the VDUP-1 promoter. The interference of PPARalpha/retinoid X receptor alpha with the AP-1 transcription factor elements c-Jun/c-Fos resulted in the inhibition of AP-1 binding and down-regulation of the VDUP-1 gene expression. Finally, PPARalpha activation reduced the lidocaine-induced caspase-3 activity and apoptosis, which might be due to the VDUP-1-mediated regulation of the Bax/Bcl-2 ratio. Together these data indicate that stimulation of PPARalpha in human macrophages might reduce arterial inflammation through differential regulation of the Trx-1 and VDUP-1 gene expression.

The regulation of cellular reduction/oxidation (redox) balance is critically determined by several antioxidant systems such as the thioredoxin-1 (Trx-1) which reduces disulfides on targeted proteins. In addition, intracellular Trx-1 exerts most of its antioxidant properties through scavenging of reactive oxygen species. Moreover, it acts as a cofactor for several enzymes and plays an important role in the regulation of redox-sensitive transcription factors. Several studies have reported that Trx-1 activity can be modulated by the interaction with vitamin D3-upregulated protein (VDUP-1) (also called Txnip for thioredoxin interacting protein-1 or TBP-2 for Trx-binding protein-2). Trx-1 secretion has been reported to occur in conditions associated with oxidative stress and inflammation. Beneficial effects of elevated plasma Trx-1 levels on various pathologies were reported in mice. In conclusion, oxidative stress is an important actor in various pathologies including cardio- and cerebro-vascular diseases. Therefore, controlling the redox status by increasing the activity of Trx-1 seems to be a novel and an attractive approach.

MMP-12, a macrophage-specific matrix metalloproteinase with large substrate specificity, has been reported to be highly expressed in mice, rabbits and human atherosclerotic lesions. Increased MMP-12 from inflammatory macrophages is associated with several degenerative diseases such as atherosclerosis. In this manuscript, we show that IL-1beta, a proinflammatory cytokine found in atherosclerotic plaques, increases both mRNA and protein levels of MMP-12 in human monocyte-derived macrophages (HMDM). Since peroxisome proliferator-activated receptors (PPARs), such as PPARalpha and PPARgamma, are expressed in macrophages and because PPAR activation exerts an anti-inflammatory effect on vascular cells, we have investigated the effect of PPARalpha and gamma isoforms on MMP-12 regulation in HMDM. Our results show that MMP-12 expression (mRNA and protein) is down regulated in IL-1beta-treated macrophages only in the presence of a specific PPARalpha agonist, GW647, in a dose-dependent manner. In contrast, this inhibitory effect was abolished in IL-1beta-stimulated peritoneal macrophages isolated from PPARalpha(-/-) mice and treated with the PPARalpha agonist, GW647. Moreover, reporter gene transfection experiments using different MMP-12 promoter constructs showed a reduction of the promoter activities by approximately 50% in IL-1beta-stimulated PPARalpha-pre-treated cells. However, MMP-12 promoter analysis did not reveal the presence of a PPRE response element. The IL-1beta effect is known to be mediated through the AP-1 binding site. Mutation of the AP-1 site, located at -81 in the MMP-12 promoter region relative to the transcription start site, followed by transfection analysis, gel shift and ChIP experiments revealed that the inhibitory effect was the consequence of the protein-protein interaction between GW 647-activated PPARalpha and c-Fos or c-Jun transcription factors, leading to inhibition of their binding to the AP-1 motif. These studies suggest that PPARalpha agonists may be used therapeutically, not only for lipid disorders, but also to prevent inflammation and atheromatous plaque rupture, where their ability to inhibit MMP-12 expression in HMDM may be beneficial.

Objective— In this article, we studied the effect of acetyl-11-keto-β-boswellic acid (AKβBA), a natural inhibitor of the proinflammatory transcription factor NF-κB on the development of atherosclerotic lesions in apolipoprotein E–deficient (apoE −/− ) mice. Methods and Results— Atherosclerotic lesions were induced by weekly LPS injection in apoE −/− mice. LPS alone increased atherosclerotic lesion size by ≈100%, and treatment with AKβBA significantly reduced it by ≈50%. Moreover, the activity of NF-κB was also reduced in the atherosclerotic plaques of LPS-injected apoE −/− mice treated with AKβBA. As a consequence, AKβBA treatment led to a significant downregulation of several NF-κB–dependent genes such as MCP-1, MCP-3, IL-1α, MIP-2, VEGF, and TF. By contrast, AKβBA did not affect the plasma concentrations of triglycerides, total cholesterol, antioxidized LDL antibodies, and various subsets of lymphocyte-derived cytokines. Moreover, AKβBA potently inhibited the IκB kinase (IKK) activity immunoprecipitated from LPS-stimulated mouse macrophages and mononuclear cells leading to decreased phosphorylation of IκBα and inhibition of p65/NF-κB activation. Comparable AKβBA-mediated inhibition was also observed in LPS-stimulated human macrophages. Conclusion— The inhibition of NF-κB activity by plant resins from species of the Boswellia family might represent an alternative for classical medicine treatments for chronic inflammatory diseases such as atherosclerosis. (Arterioscler Thromb Vasc Biol. 2008;28:272-277)

Bacillus thuringiensis subsp. kurstaki BUPM255 secretes a chitobiosidase Chi255 having an expected molecular weight of 70.665 kDa. When the corresponding gene, chi255, was expressed in E. coli, the active form, extracted from the periplasmic fraction of E. coli/pBADchi255, was of about 54 kDa, which suggested that Chi255 was excessively degraded by the action of E. coli proteases. Therefore, in vitro progressive C-terminal Chi255 deleted derivatives were constructed in order to study their stability and their activity in E. coli. Interestingly, when the chitin binding domain (CBD) was deleted from Chi255, an active form (Chi2555Delta5) of expected size of about 60 kDa was extracted from the E. coli periplasmic fraction, without the observation of any proteolytic degradation. Compared to Chi255, Chi255Delta5 exhibited a higher chitinase activity on colloidal chitin. Both of the enzymes exhibit activities at broad pH and temperature ranges with maximal enzyme activities at pH 5 and pH 6 and at temperatures 50 degrees C and 40 degrees C, respectively for Chi255 and Chi255Delta5. Thus, it was concluded that the C-terminal deletion of Chi255 CBD might be a nice tool for avoiding the excessive chitinase degradation, observed in the native chitinase, and for improving its activity.

A sensing material based on calix[4]arene molecules (Azo-C[4]) dispersed in a conjugated polymer (MEHPPV) is deposited by spin coating onto a transparent conducting substrate (ITO) to fabricate new chemical sensors. The electrochemical properties of the sensor are investigated by impedance spectroscopy. Transfer and ion diffusion processes of metal cations (Cu2+, Eu3+) in the Azo-C[4]-MEHPPV membranes are studied. The calixarene molecule behaviour into the polymer membranes is characterised by impedance spectroscopy showing the cation complexation by both, Azo-calix[4]arene and MEHPPV, components of the membrane. The differences in selectivity are found to be represented by variations in the bulk resistance of the membrane (Rm) and in the charge transfer resistance (Rtc) of the interface. The impedance behaviour of the Azo-C[4]-MEHPPV electrodes is modelled by an equivalent electrical circuit. Optical excitation tests of these membranes show that the sensing activity of the calixarene molecules entrapped in the polymer matrix is preserved.

Unlike classical digestive lipases, the scorpion digestive lipase (SDL) has a strong basic character. The SDL activity's optimal pH, when using tributyrin or olive oil as substrate, was 9.0. Added to that, the estimated isoelectric point of the native SDL using the electrofocusing technique, was found to be higher than 9.6. To our knowledge, this is the first report of an animal digestive lipase having such a basic character. When olive oil was used as substrate, SDL was shown to be insensitive to the presence of amphiphilic proteins such as bovine serum albumin (BSA). Furthermore, the hydrolysis was found to be specifically dependent on the presence of Ca2+ ions, since no significant SDL activity was detected in the presence of ions chelator such as EDTA. Nevertheless, the SDL does not require Ca2+ to trigger the hydrolysis of tributyrin emulsion. Interestingly Zn2+ and Cu2+ ions act as strong inhibitors of SDL activity when using tributyrin as substrate. An internal chymotryptic cleavage of SDL generated two fragments of 28 and 25 kDa having the same N-terminal sequence. This sequence of 19 residues does not share any homology with known animal and microbial lipases. Polyclonal antibodies directed against SDL (pAbs anti-SDL) failed to recognise ostrich pancreatic and dog gastric lipases (OPL and rDGL). Moreover, both pAbs anti-OPL and anti-rDGL failed to immunoreact with SDL. These immunological as well as distinct biochemical properties strengthen the idea that SDL appears to belong to a new invertebrate's lipase group.

The fate and phenotype of lesion macrophages is regulated by cellular oxidative stress. Thioredoxin-1 (Trx-1) plays a major role in the regulation of cellular redox balance, with resultant effects on gene expression and cellular responses including cell growth and death. Trx-1 activity is inhibited by interaction with vitamin D-upregulated protein-1 (VDUP-1). Peroxisome proliferator-activated receptor gamma (PPARgamma) is expressed by human monocyte-derived macrophages (HMDM) and PPARgamma agonism has been reported to decrease expression of inflammatory genes and to promote apoptosis of these cells. To determine whether VDUP-1 may be involved in regulating the effects of PPARgamma agonists in macrophages, we investigated the effect of a synthetic PPARgamma agonist (GW929) on the expression of VDUP-1 in HMDM. GW929 concentration-dependently increased HMDM expression of VDUP-1 (mRNA and protein). Transfection of different fragments of the VDUP-1 promoter as well as gel shift analysis revealed the presence of functional PPARgamma response elements (PPRE) in the promoter. Under conditions in which PPAR agonism altered levels of VDUP-1, caspase-3 activity, and macrophage apoptosis were also elevated. The results suggest that PPARgamma activation stimulates apoptosis in human macrophages by altering the cellular redox balance via regulation of VDUP-1.

The essential oils of the Tunisian Allium roseum flowers and stems gathered in the region of Monastir and obtained by hydrodistillation with 0.012% and 0.002% yield, respectively, were analyzed by GC and GC-MS. Some significant differences were found between the constituent percentages of flowers and stems essential oils. Ten sulphur compounds representing 60.97% of the total constituents have been identified in the flower oil. The main components found in this organ were allyl methyl disulphide (16.06%) and diallyl disulphide (16.57%). Six sulphur compounds representing 11.2% of all the components of the stem volatile fraction were characterized. The latter was rich in fatty acid esters, they represent 65.23% of all its components. Flowers oil was richer in sulphur compounds than stems oil and the two main sulphur compounds allyl methyl disulphide and diallyl disulphide in the flowers oil did not exist in significant amount in the case of stems oil.

Objective— Recent studies have provided strong evidence for the presence of ozone in atherosclerotic lesions. In addition, modification of LDL has been suggested to be involved in atherosclerosis. In the present study we wanted to investigate whether LDL exposed to ozone (ozLDL) is able to modulate the NF-κB system, as a paradigm for inflammatory signaling. Methods and Results— We showed that activation of NF-κB by lipopolysaccharide (LPS), a prototypic inducer of innate immunity, was reversibly inhibited by ozLDL in monocytic THP-1 cells in a dose-dependent manner, whereas tumor necrosis factor (TNF) signaling was not affected. This was not attributable to a direct ozone effect or solely the presence of lipoprotein, and neither required direct contact to LPS nor was accompanied by a change in LPS binding. Comparable inhibitory effects of ozLDL were observed in human monocyte/macrophages and endothelial cells. The presence of ozLDL led to a decrease in LPS-induced IκΒα proteolysis and a reduction of κB-dependent transcription/target-gene expression. Furthermore, ozLDL markedly lowered stimulus-induced IκΒ kinase (IKK) activity and phosphorylation/proteolysis of interleukin (IL)-1 receptor-associated kinase-1 (IRAK-1). Finally, cholesterol ozonization products were identified as effective ozLDL inhibitory compounds. Conclusion— Our study demonstrated that ozLDL inhibited NF-κB and IRAK-1–associated signaling which may impair immune function and promote apoptosis.

In response to the letter of Drs Takahashi and Karasawa, we thought it might be of interest to open the debate about the mechanism by which arglabin, a natural compound isolated from Artemisia glabella , inhibits cholesterol crystal–induced activation of the NLRP3 inflammasome in murine macrophages. In the March 2015 online issue of Circulation 1 we evaluated the impact of arglabin on cholesterol crystal–mediated NLRP3 activation in cultured murine macrophages and in ApoE2.Ki mice fed a high-fat diet. We showed that both Nlrp3 knockout and inhibition of NLRP3 activation by the compound arglabin significantly decreased the size of atherosclerotic lesions in ApoE2.Ki mice fed a high-fat diet. At the molecular level, arglabin inhibited the activity of the NLRP3 inflammasome and significantly reduced the subsequent production of interleukin 1β (IL-1β) and interleukin 18 in vitro …

A novel optical sensor for sensitive and selective determination of copper ions in aqueous solution based on a novel calix[4]dicyano-diimidazole ionophore was prepared. The newly synthesized calix[4]dicyano-diimidazole exhibited obvious absorbance enhancement at 284 nm in the presence of copper ions. At pH 6.8, the measuring range of the optode membrane for Cu 2+ ions was from 1.0 × 10 −8 to 1.0 × 10 −4 M with a detection limit of 7.0 × 10 −9 M. Furthermore, the response time of the proposed optical device was within 10 min. With the optimum condition described, the optical sensor revealed good selectivity toward Cu 2+ ions in comparison with common coexisting cations (Hg 2+ , Pb 2+ , Cd 2+ , Ni 2+ and Zn 2+ ). Finally, the reproducibility, regeneration, reversibility and repeatability of this optical sensor were discussed.

International audience; Secretory Phospholipase A2 of type IIA (sPLA2 IIA) plays a crucial role in the production of lipid mediators by amplifying the neointimal inflammatory context of the vascular smooth muscle cells (VSMCs), especially during atherogenesis. Phenformin, a biguanide family member, by its anti-inflammatory properties presents potential for promoting beneficial effects upon vascular cells, however its impact upon the IL-1β-induced sPLA2 gene expression has not been deeply investigated so far. The present study was designed to determine the relationship between phenformin coupling AMP-activated protein kinase (AMPK) function and the molecular mechanism by which the sPLA2 IIA expression was modulated in VSMCs. Here we find that 5-aminoimidazole-4-carboxamide-1-β-D-ribonucleotide (AICAR) treatment strongly repressed IL-1β-induced sPLA2 expression at least at the transcriptional level. Our study reveals that phenformin elicited a dose-dependent inhibition of the sPLA2 IIA expression and transient overexpression experiments of constitutively active AMPK demonstrate clearly that AMPK signaling is involved in the transcriptional inhibition of sPLA2-IIA gene expression. Furthermore, although the expression of the transcriptional repressor B-cell lymphoma-6 protein (BCL-6) was markedly enhanced by phenformin and AICAR, the repression of sPLA2 gene occurs through a mechanism independent of BCL-6 DNA binding site. In addition we show that activation of AMPK limits IL-1β-induced NF-κB pathway activation. Our results indicate that BCL-6, once activated by AMPK, functions as a competitor of the IL-1β induced NF-κB transcription complex. Our findings provide insights on a new anti-inflammatory pathway linking phenformin, AMPK and molecular control of sPLA2 IIA gene expression in VSMCs.

The Bacillus thuringiensis subsp. kurstaki strain MEB4 was previously found to be highly toxic to Ephestia kuehniella. SDS-PAGE analysis of the recombinant strain DH5α (pBS-cry2Aa-MEB4) showed that Cry2Aa-MEB4 delta-endotoxins were forming inclusion bodies, and were 2.75 fold more toxic towards E. kuehniella than those of Cry2Aa-BNS3. Besides to the 65kDa active toxin, proteolysis activation of Cry2Aa-BNS3 protein with E. kuehniella midgut juice generated an extra proteolysis form of 49kDa, which was the result of another chymotrypsin cleavage located in Leu144. The amino acid sequences alignment of Cry2Aa-MEB4 and Cry2Aa-BNS3 showed that among the different 15 amino acids, the Q139R substitution was found to be interesting. In fact, due to its presence within the loop α3-α4, the chymotrypsin-like protease was unable to access to its site in Cry2Aa-MEB4, resulting to the production of only the 65kDa form. The accessible surface and the stability studies of the structure model of the Cry2Aa-BNS3-49 form showed a lower hydrophobicity surface due to the omission of 144 amino acids from the N-terminal comparing with the active Cry2Aa-MEB4 protein. All these features caused the diminishing of Cry2Aa-BNS3 toxicity towards E. kuehniella.

Acacia cyanophylla Lindl. (Fabaceae), synonym Acacia saligna (Labill.) H. L.Wendl., native to West Australia and naturalized in North Africa and South Europe, was introduced in Tunisia for rangeland rehabilitation, particularly in the semiarid zones. In addition, this evergreen tree represents a potential forage resource, particularly during periods of drought. A. cyanophylla is abundant in Tunisia and some other Mediterranean countries. The chemical composition of the essential oils obtained by hydrodistillation from different plant parts, viz., roots, stems, phyllodes, flowers, and pods (fully mature fruits without seeds), was characterized for the first time here. According to GC-FID and GC/MS analyses, the principal compound in the phyllode and flower oils was dodecanoic acid (4), representing 22.8 and 66.5% of the total oil, respectively. Phenylethyl salicylate (8; 34.9%), heptyl valerate (3; 17.3%), and nonadecane (36%) were the main compounds in the root, stem, and pod oils, respectively. The phyllode and flower oils were very similar, containing almost the same compounds. Nevertheless, the phyllode oil differed from the flower oil for its higher contents of hexahydrofarnesyl acetone (6), linalool (1), pentadecanal, α-terpineol, and benzyl benzoate (5) and its lower content of 4. Principal component and hierarchical cluster analyses separated the five essential oils into four groups, each characterized by its main constituents. Furthermore, the allelopathic activity of each oil was evaluated using lettuce (Lactuca sativa L.) as a plant model. The phyllode, flower, and pod oils exhibited a strong allelopathic activity against lettuce.

Abnormal lipid deposition in human arteries leads to the formation of fatty streaks due to the accumulation of a large number of macrophage derived-foam cells. The formation and catabolism of intracellular lipid droplets is regulated by droplet-associated proteins. Among such proteins, the role of perilipin in human macrophages was unknown. In this study, we first showed that perilipin expression was increased during differentiation of human monocytes to macrophages. Interestingly, cellular perilipin content was unaffected by treatment of cells with OxLDL, AcLDL, VLDL or sterol esters. Moreover, its expression was not dependent on the presence of adipophilin, another lipid droplet-associated protein, since it was not affected by transfection of macrophages with siRNA-adipophilin. Perilipin overexpression in macrophages with an expression vector resulted in significant lipid droplet formation and TG accumulation and this was unaffected by decreasing adipophilin levels using siRNA. Consequently, perilipin, like adipophilin, might play an important role in the conversion of macrophages into foam cells and contribute to lesion formation. Therefore, inhibition of adipophilin might not be sufficient to prevent lesion formation as previously suggested, and perilipin inhibition might be additionally required.

Human data raised the possibility that coronary heart disease is associated with mutations in the apolipoprotein gene cluster APOA1/C3/A4 that result in multideficiency of cluster-encoded apolipoproteins and hypoalphalipoproteinemia. To test this hypothesis, we generated a mouse model for human apolipoprotein A-I (apoA-I)/C-III/A-IV deficiency. Homozygous mutants (Apoa1/c3/a4−/−) lacking the three cluster-encoded apolipoproteins were viable and fertile. In addition, feeding behavior and growth were apparently normal. Total cholesterol (TC), high density lipoprotein cholesterol (HDLc), and triglyceride levels in the plasma of fasted mutants fed a regular chow were 32% (P < 0.001), 17% (P < 0.001), and 70% (P < 0.01), respectively, those of wild-type mice. When fed a high-fat Western-type (HFW) diet, Apoa1/c3/a4−/− mice showed a further decrease in HDLc concentration and a moderate increase in TC, essentially in non-HDL fraction. The capacity of Apoa1/c3/a4−/− plasma to promote cholesterol efflux in vitro was decreased to 75% (P < 0.001), and LCAT activity was decreased by 38% (P < 0.01). Despite the very low total plasma cholesterol, the imbalance in lipoprotein distribution caused small but detectable aortic lesions in one-third of Apoa1/c3/a4−/− mice fed a HFW diet. In contrast, none of the wild-type mice had lesions. These results demonstrate that Apoa1/c3/a4−/− mice display clinical features similar to human apoA-I/C-III/A-IV deficiency (i.e., marked hypoalphalipoproteinemia) and provide further support for the apoa1/c3/a4 gene cluster as a minor susceptibility locus for atherosclerosis in mice.

New chromogenic calix[4]arene derivatives proved many applications in optical and electrical fields. Organic diodes formed by sandwiching azo-calix[4]arene layers between indium-thin oxide (ITO) and (Al) contacts have been elaborated and measured. In this paper, studies of devices by current–voltage characteristics I(V) and electrical impedance spectroscopy measurements in a wide frequency range have been reported. The electrical characteristics follow a space charge limited conduction behaviour (SCLC). Therefore, the Cole–Cole plots were modelled by an equivalent circuit. Relaxation processes have been identified too from the impedance spectroscopy. The optical excitation of the organic structure revealed enhancement in electrical properties.

N. ABID, S. MAALEJ AND S. ROUIS. 2004. Aims: To characterize hypochlorous acid (HOCl) stress resistance of Staphylococcus aureus and to assessphysiological state and changes in cell morphology.Methods and Results: Clinical wild-type strain of S. aureus was used in the stress with HOCl at concentrationsranging from 0 to 4 mg l )1 . Concentrations below 1AE5mgl )1 caused no significant drop in viability. During 2 h ofHOCl stress at 2 mg l )1 , there was appearance of minicells capable of passing through the 0AE45 lm pores offiltration membranes. Intracellular proteins increased gradually to reach a level of 51% of dry weight and anenhanced synthesis of at least two proteins of 23 and 220 kDa was concluded.Conclusions, Significance and Impact of the Study: Staphylococcus aureus can undergo morphological andphysiological changes during 2 h of exposure to 2 mg l )1 of HOCl, which represents an adaptative response towardsthe hypochlorous acid stress. This evolution limits the use of 0AE45 lm pores size membrane filters for research onS. aureus in waters and the clinical environment.Keywords: adaptation, HOCl, minicells, oxidative stress, Staphylococcus aureus.

Objective— Uptake of modified low-density lipoprotein (LDL) by macrophages through scavenger receptors results in lipid droplets accumulation and foam cell formation. Excess lipid deposition in macrophages has been reported to modulate expression of several genes including adipophilin. In this study, we investigated the function of adipophilin in lipid accumulation and cholesterol efflux in THP-1 macrophages. Methods and Results— Adipophilin mRNA expression was 3.5-fold higher in human atherosclerotic plaques compared with healthy areas of the same arteries. Moreover, in the presence of acetylated LDL (AcLDL), triglycerides and cholesteryl esters were increased in macrophages overexpressing adipophilin by 40% and 67%, respectively, whereas their accumulation was reduced when endogenous cellular adipophilin was depleted using siRNA approach. In addition, neither overexpression nor downregulation of adipophilin altered expression of genes involved in lipid efflux. However, the affinity and the number of AcLDL receptors were not affected. After 24-hour incubation of lipid-loaded macrophages with apolipoprotein A-I, cholesterol efflux was reduced by 47% in adipophilin transfected cells versus control cells. Conclusion— Our results showed that stimulation of adipophilin expression in macrophages by modified LDL promotes triglycerides and cholesterol storage and reduces cholesterol efflux. Therefore, adipophilin might contribute, in vivo, to lipid accumulation in the intima of the arterial wall.

Fructose intake has increased steadily during the past two decades. The objective of this study was to determine the effect of fructose intake on lipid metabolism in apolipoprotein (apo) AI-CIII-AIV transgenic (Tg) mice that have severe hypertriglyceridemia and moderate hypercholesterolemia. Tg and control mice were fed for 9 mo a commercial nonpurified diet and had free access to water or 250 g/L fructose solution. In Tg mice, fructose intake increased triglycerides and cholesterol but did not induce insulin resistance. There were no differences in human hepatic apo AI and apo CIII mRNA levels in fructose-fed mice compared with untreated mice, but apo AIV mRNA was greater, indicating a differential expression of the apo AI and apo AIV genes in response to dietary perturbations. Interestingly, the plasma concentration of the three human apolipoproteins was enhanced in fructose-fed Tg mice compared with untreated Tg mice. Our data suggest that long-term fructose consumption had strong adverse effects in this hyperlipidemic mouse model.

In Tunisia, Tipuana tipu (Benth.) Kuntze is an exotic tree, which was introduced many years ago and planted as ornamental street, garden, and park tree. The present work reported, for the first time, the chemical composition and evaluates the allelopathic effect of the hydrodistilled essential oils of the different parts of this tree, viz., roots, stems, leaves, flowers, and pods gathered in the area of Sousse, a coastal region, in the East of Tunisia. In total, 86 compounds representing 89.9 - 94.9% of the whole oil composition, were identified in these oils by GC-FID and GC/MS analyses. The root essential oil was clearly distinguished for its high content in sesquiterpene hydrocarbons (β-caryophyllene, 1 (44); 24.1% and germacrene D, 2 (53); 20.0%), while those obtained from pods, leaves, stems, and flowers were dominated by non-terpene hydrocarbons. The most important ones were n-tetradecane (41, 16.3%, pod oil), 1,7-dimethylnaphthalene (43, 15.6%, leaf oil), and n-octadecane (77, 13.1%, stem oil). The leaf oil was rich in the apocarotene (E)-β-ionone (4 (54); 33.8%), and the oil obtained from flowers was characterized by hexahydrofarnesylacetone (5 (81); 19.9%) and methyl hexadecanoate (83, 10.2%). Principal component and hierarchical cluster analyses separated the five essential oils into three groups and two subgroups, each characterized by the major oil constituents. Contact tests showed that the germination of lettuce seeds was totally inhibited by the root essential oil tested at 1 mg/ml. The inhibitory effect on the shoot and root elongation varied from -1.6% to -32.4%, and from -2.5% to -64.4%, respectively.

Abstract —A new polymorphism located at position −629 (CETP/−629A/C) in the promoter of the cholesteryl ester transfer protein (CETP) gene is described. The −629A allele was associated with lower CETP mass ( P P P P