Herbal plants in the traditional medicine of Bahrain

Plant samples collected in Bahrain and data reported in the literature indicate the flora of Bahrain to contain 52 species (49 genera; 20 families) of medicinal interest. Of these plant species 20 appear to be indigenous and are being used in traditional herbal remedies for numerous afflictions. Preparation of such remedies appears to be simple and includes boiling, infusions, extraction of milled dry or fresh leaves, flowers, seeds or whole plants. Direct consumption of plant parts, raw or cooked, is also practiced. None of these plants has been studied systematically to evaluate their medicinal potential.     

Methoxycamalexins and related compounds: Syntheses,antifungal activity and inhibition of brassinin oxidase

The phytoalexin camalexin is a competitive inhibitor of brassinin oxidase, an enzyme that detoxifies the phytoalexin brassinin and is produced by an economically important plant pathogen. For this reason, the camalexin scaffold has guided the design of inhibitors of brassinin detoxification. To further understand the structure–activity relationships of camalexin related compounds, the syntheses of monomethoxy and dimethoxycamalexins were undertaken. Four monomethoxy camalexins together with 4,6-dimethoxy and 5,7-dimethoxy camalexins were prepared from the corresponding methoxyindoles using the Ayer's method. The dimethoxy derivatives were prepared from the corresponding dimethoxyindole-3-thiocarboxamides using the Hantzsch reaction; however, this method did not work for the syntheses of 4,6-dimethoxy and 5,7-dimethoxycamalexins due to the lower reactivities of the corresponding indole-3-thiocarboxamides. The antifungal activity and brassinin oxidase inhibitory activity of all methoxycamalexins and ten camalexin related compounds were investigated. Among the 20 compounds evaluated, monomethoxycamalexins were stronger antifungals than the dimethoxy derivatives. However, remarkably, 5,6-dimethoxycamalexin, 6,7-dimethoxycamalexin and 5-methoxycamalexin displayed the strongest inhibitory activity against brassinin oxidase, while 4,5-dimethoxycamalexin displayed no inhibitory effect. Altogether the structure–activity relationships of camalexin related compounds suggest that the targets for fungal growth inhibition and brassinin oxidase inhibition are unrelated and emphasize that brassinin oxidase inhibitors do not need to be antifungal.     

Landscape fragmentation generates spatial variation of diet composition and quality in a generalist herbivore

Forest fragmentation may benefit generalist herbivores by increasing access to various substitutable food resources, with potential consequences for their population dynamics. We studied a European roe deer (Capreolus capreolus) population living in an agricultural mosaic of forest, woodlots, meadows and cultivated crops. We tested whether diet composition and quality varied spatially across the landscape using botanical analyses of rumen contents and chemical analyses of the plants consumed in relation to landscape metrics. In summer and non-mast winters, roe deer ate more cultivated seeds and less native forest browse with increasing availability of crops in the local landscape. This spatial variation resulted in contrasting diet quality, with more cell content and lower lignin and hemicellulose content (high quality) for individuals living in more open habitats. The pattern was less marked in the other seasons when diet composition, but not diet quality, was only weakly related to landscape structure. In mast autumns and winters, the consumption of acorns across the entire landscape resulted in a low level of differentiation in diet composition and quality. Our results reflect the ability of generalist species, such as roe deer, to adapt to the fragmentation of their forest habitat by exhibiting a plastic feeding behavior, enabling them to use supplementary resources available in the agricultural matrix. This flexibility confers nutritional advantages to individuals with access to cultivated fields when their native food resources are depleted or decline in quality (e.g. during non-mast years) and may explain local heterogeneities in individual phenotypic quality.     

An exact analysis for a solute transport,due to simultaneous dialysis and ultrafiltration,in a hollow-fibre artificial kidney

Transport of a uremic solute effected by a combined dialysis and ultrafiltration procedure in a hollow-fibre artificial kidney, is investigated theoretically under standard assumptions. An exact analytical solution for the concentration profile in a blood channel is obtained by using the method of separation of variables. The necessary requirement that the solution must tend to that of pure dialysis, in the limit ultrafiltration tending to zero, is fulfilled. Exact analytical expressions are derived for the eigenconstants of the solution. In using the solution, the solute clearance is emphasized. Diffusive and ultrafiltration components of the solute clearance are defined and studied. The combined procedure is examined for middle versus small molecules and for polyacrylonitrile versus cuprophan hollow-fibres.     

Cytoplasmic tail deletion converts membrane immunoglobulin to a phosphatidylinositol-linked form lacking signaling and efficient antigen internalization functions

Membrane-bound immunoglobulin (mIg) is the antigen receptor on B lymphocytes mediating early events in antigen presentation and signal transduction. Wild-type human mIgM constructs transfected into the murine B-cell lymphoma A20 are expressed as transmembrane proteins with antigen presentation and signaling functions comparable to the endogenous mIgG2A; the transfected wild-type mIgM is internalized rapidly after anti-Ig cross-linking. Transfected constructs lacking the normal three-amino acid cytoplasmic tail are expressed exclusively as phosphatidylinositol-linked proteins, lack both antigen presentation and signal transduction functions, and are internalized slowly following anti-Ig binding. The molecular mass of the cytoplasmic tail-deleted phosphatidylinositol-linked Ig molecule is consistent with cleavage of the transmembrane residues during processing. Cytoplasmic domains may therefore regulate the mode of expression of membrane proteins and thereby influence their functional capabilities.     

Overview of Strain Characterization in Relation to Serological and Molecular Detection of Citrus tristeza <i>Closterovirus</i>

Tristeza is a devastating viral disease in all the citrus growing countries throughout the world and has killed millions of citrus trees in severely affected orchards. The citrus species grafted on sour orange rootstock are affected by this disease. Predominantly, the sweet orange, grapefruit and lime trees grafted on sour orange exhibit severe symptoms like quick decline, vein clearing, pin holing, bark scaling and degeneration leading to variable symptoms. Symptomatic expression of Citrus tristeza virus (CTV) in different hosts has been attributed to virus isolates which are from severe to mild. Different serological and molecular assays have been deployed to differentiate the strains of CTV. Citrus tristeza virus is diversified towards its strains on the basis of biological, serological and molecular characterization. Phenotypic expression is due to genetic alteration and different molecular basis have now been adopted for strain differentiation. This review will give a brief idea about the different CTV isolates, their characterization based on nucleic acid and serological assays. Different methods along with salient features for strain characterization has also been reviewed. This review will also open the new aspects towards formulation of management strategies through different detection techniques.     

First DNA Barcoding-based Inventory of Suez Gulf Fishes in Egypt and its Implication for Species Diversity

Journal of Ichthyology - The Suez Gulf is one of the most important water bodies north of the Red Sea that contribute significantly in fish production in Egypt. The current study represents the...     

Elucidating Cd-mediated distinct rhizospheric and in planta ionomic and physio-biochemical responses of two contrasting Zea mays L. cultivars

Cadmium (Cd) in soil–plant system can abridge plant growth by initiating alterations in root zones. Hydroponics and rhizoboxes are useful techniques to monitor plant responses against various natural and/or induced metal stresses. However, soil based studies are considered more appropriate in order to devise efficient food safety and remediation strategies. The present research evaluated the Cd-mediated variations in elemental dynamics of rhizospheric soil together with in planta ionomics and morpho-physio-biochemical traits of two differentially Cd responsive maize cultivars. Cd-sensitive (31P41) and Cd-tolerant (3062) cultivars were grown in pots filled with 0, 20, 40, 60 and 80 µg/kg CdCl₂ supplemented soil. The results depicted that the maize cultivars significantly influenced the elemental dynamics of rhizosphere as well as in planta mineral accumulation under applied Cd stress. The uptake and translocation of N, P, K, Ca, Mg, Zn and Fe from rhizosphere and root cell sap was significantly higher in Cd stressed cv. 3062 as compared to cv. 31P41. In sensitive cultivar (31P41), Cd toxicity resulted in significantly prominent reduction of biomass, leaf area, chlorophyll, carotenoids, protein contents as well as catalase activity in comparison to tolerant one (3062). Analysis of tolerance indexes (TIs) validated that cv. 3062 exhibited advantageous growth and efficient Cd tolerance due to elevated proline, phenolics and activity of antioxidative machinery as compared to cv. 31P41. The cv. 3062 exhibited 54% and 37% less Cd bio-concentration (BCF) and translocation factors (TF), respectively in comparison to cv. 31P41 under highest Cd stress regime. Lower BCF and TF designated a higher Cd stabilization by tolerant cultivar (3062) in rhizospheric zone and its potential use in future remediation plans.     

Synthesis,anticancer activity,and β‐lactoglobulin binding interactions of multitargeted kinase inhibitor sorafenib tosylate (SORt) using spectroscopic and molecular modelling approaches

Sorafenib tosylate (SORt) is an oral multikinase inhibitor used for treatment of advanced renal cell, liver, and thyroid cancers. In this study, this drug was synthesized and its antiproliferative activities against HCT116 and CT26 cells were assessed. The interaction of SORt with β‐lactoglobulin (BLG) was studied using different fluorescence techniques, circular dichroism (CD), zeta potential measurements, and docking simulation. The results of infrared (IR), mass, ^HNMR, and ^CNMR spectra demonstrated that the drug was produced with high quality, purity, and efficiency. SORt showed potent cytotoxicity against HCT116 and CT26 cells with IC₅₀ of 8.12 and 5.42 μM, respectively. For BLG binding of SORt, the results showed that static quenching was the cause of the high affinity drug–protein interaction. Three‐dimensional fluorescence and synchronous spectra indicated that SORt conformation was changed at different levels. CD suggested that the α‐helix content remained almost constant in the BLG–SORt complex, whereas random coil content decreased. Zeta potential values of BLG were more positive after binding with SORt, due to electrostatic interactions between BLG and SORt. Thermodynamic parameters confirmed van der Waals and hydrogen bond interactions in the complex formation. Molecular modelling predicted the presence of hydrogen bonds and electrostatic forces in the BLG–SORt system, which was consistent with the experimental results.