Rhizobia utilize pathogen-like effector proteins during symbiosis

A type III protein secretion system (T3SS) is an important host range determinant for the infection of legumes by Rhizobium sp. NGR234. Although a functional T3SS can have either beneficial or detrimental effects on nodule formation, only the rhizobial-specific positively acting effector proteins, NopL and NopP, have been characterized. NGR234 possesses three open reading frames potentially encoding homologues of effector proteins from pathogenic bacteria. NopJ, NopM and NopT are secreted by the T3SS of NGR234. All three can have negative effects on the interaction with legumes, but NopM and NopT also stimulate nodulation on certain plants. NopT belongs to a family of pathogenic effector proteases, typified by the avirulence protein, AvrPphB. The protease domain of NopT is required for its recognition and a subsequent strong inhibition in infection of Crotalaria juncea . In contrast, the negative effects of NopJ are relatively minor when compared with those induced by its Avr homologues. Thus NGR234 uses a mixture of rhizobial-specific and pathogen-derived effector proteins. Whereas some legumes recognize an effector as potentially pathogen-derived, leading to a block in the infection process, others perceive both the negative- and positive-acting effectors concomitantly. It is this equilibrium of effector action that leads to modulation of symbiotic development.     

Development of a Mini-Freeze Dryer for Material-Sparing Laboratory Processing with Representative Product Temperature History

The goal of the work described in this publication was to evaluate a new, small, material-sparing freeze dryer, denoted as the “mini-freeze dryer or mini-FD”, capable of reproducing the product temperature history of larger freeze dryers, thereby facilitating scale-up. The mini-FD wall temperatures can be controlled to mimic loading procedures and dryer process characteristics of larger dryers. The mini-FD is equipped with a tunable diode laser absorption spectroscopy (TDLAS) water vapor mass flow monitor and with other advanced process analytical technology (PAT) sensors. Drying experiments were performed to demonstrate scalability to larger freeze dryers, including the determination of vial heat transfer coefficients, K _v . Product temperature histories during K _v runs were evaluated and compared with those obtained with a commercial laboratory-scale freeze dryer (LyoStar II) for sucrose and mannitol product formulations. When the mini-FD wall temperature was set at the LyoStar II band temperature (? 20°C) to mimic lab dryer edge vials, edge vial drying in the mini-FD possessed an average K _v within 5% of those obtained during drying in the LyoStar II. When the wall temperature of the mini-FD was set equal to the central vial product temperature, edge vials behaved as center vials, possessing a K _v value within 5% of those measured in the LyoStar II. During both K _v runs and complete product freeze drying runs, the temperature-time profiles for the average edge vials and central vial in the mini-FD agreed well with the average edge and average central vials of the LyoStar II.     

Synthesis,optical properties and cytotoxicity of meso-heteroatom substituted IR-786 analogs

Eight near-infrared heptamethine cyanines have been successfully synthesized based on IR 786 with oxygen, sulfur and amine moieties at the central position. These dyes show diverse optical properties resulting from different substitutions. Particularly, the heptamethine dyes with amine moieties have larger Stokes shifts and higher quantum yields of fluorescence. We also investigated these dyes for tumor cell cytotoxicity using cell viability and in vitro proliferation assays. Two of the compounds showed high cytotoxicity against PC-3 cancer cells.     

Odd-chain polyunsaturated fatty acids in thraustochytrids

A series of unusual odd-chain fatty acids (OC-FA) were identified in two thraustochytrid strains, TC 01 and TC 04, isolated from waters off the south east coast of Tasmania, Australia. FA compositions were determined by capillary GC and GC–MS, with confirmation of polyunsaturated fatty acids (PUFA) structure performed by analysis of 4,4-dimethyloxazoline derivatives. PUFA constituted 68–74% of the total FA, with the essential PUFA; eicosapentaenoic acid (20:5ω3, EPA), arachidonic acid (20:4ω6, AA) and docosahexaenoic acid (22:6ω3, DHA), accounting for 42–44% of the total FA. High proportions of the saturated OC-FA 15:0 (7.1% in TC 01) and 17:0 (6.2% in TC 04) were detected. The OC-FA 17:1ω8 was present at 2.8% in TC 01. Of particular interest, the C₂₁ PUFA 21:5ω5 and 21:4ω7 were detected at 3.5% and 4.1%, respectively, in TC 04. A proposed biosynthesis pathway for these OC-PUFA is presented. It is possible that the unsaturated OC-PUFA found previously in a number of marine animals were derived from dietary thraustochytrids and they could be useful biomarkers in environmental and food web studies.     

Evaluation of Matrix Tablets Based on Eudragit?E100/Carbopol?971P Combinations for Controlled Release and Improved Compaction Properties of Water Soluble Model Drug Paracetamol

The purpose of this work was to investigate the influence of Eudragit®E100 polymer in modifying the release rates and compaction properties of water soluble model drug paracetamol from Carbopol®971P NF polymer matrix tablets prepared by direct compression. The effects of the ratio of the two polymers, the total polymeric content, and the tablets mechanical strength on paracetamol release rates were investigated. Dissolution studies were conducted using USP XX Π rotating paddle apparatus at 50 rpm and 37°C at three different stages (pH 1.2, 4.8, and 6.8). Results showed that the polymers combination improved significantly the compaction properties of paracetamol tablets as evident by the higher crushing strengths (8.3 ± 0.4 Kp) compared to polymer-free tablets (3.4 ± 0.2 Kp) at intermediate compression pressure of 490 MPa. When combined with Carbopol®971P NF, Eudragit®E100 was found to be capable of extending paracetamol release for more than 12 h compared to 1 h for polymers-free tablets. The combined polymers were able to control paracetamol release in a pH independent pattern. The f2 (similarity factor) analysis showed that the ratio between the polymers and the total polymer concentration exhibited significant impact on drug release rates. In conclusion, Eudragit®E100 when combined with Carbopol®971P NF was capable of improving the compaction and sustained release properties of paracetamol. Korsmeyer–Peppas model was found to be the most suitable for fitting drug release data. The polymer combinations can potentially be used to control the release rates of highly water soluble drugs.KEY WORDS: Carbopol®971P NF, Eudragit®E100, matrix tablet, pH-independent release, sustained     

Isolation and Characterisation of a High-Efficiency Desaturase and Elongases from Microalgae for Transgenic LC-PUFA Production

The production of long-chain polyunsaturated fatty acids from precursor molecules linoleic acid (LA; 18:2ω6) and α-linolenic acid (ALA; 18:3ω3) is catalysed by sequential desaturase and elongase reactions. We report the isolation of a front-end Δ6-desaturase gene from the microalgae Ostreococcus lucimarinus and two elongase genes, a Δ6-elongase and a Δ5-elongase, from the microalga Pyramimonas cordata. These enzymes efficiently convert their respective substrates when transformed in yeast (39–75% conversion for ω3 substrate fatty acids), and the Δ5-elongase in particular displays higher elongation efficiency (75% for conversion of eicosapentaenoic acid (20:5ω3) to docosapentaenoic acid (22:5ω3)) than previously reported genes. In addition, the Δ6-desaturase is homologous with acyl-CoA desaturases and shows a strong preference for the ω3 substrate ALA.     

Monitoring treatment response of childhood acute lymphocytic leukemia with certain molecular and biochemical markers

Apoptosis is the primary mechanism through which most chemotherapeutic agents induce tumor cell death. The purpose of this study was to monitor the expression of pro- and anti-apoptotic proteins CD(95) , Bcl-2, as well as copper and zinc levels in the peripheral blood of children with acute lymphocytic leukemia (ALL) prior to and 6 months after the beginning of chemotherapy. Blood parameters and bone marrow blast count were also assessed. Twenty of 26 patients who received treatment showed amelioration in apoptotic response, which is reflected in the elevation of CD(95) , whereas Bcl-2 protein was significantly lowered. In these patients, the elevated serum copper level was not significantly affected whereas the low serum zinc level was significantly raised. Improvement in blood parameters and bone marrow blast count were also achieved. Taken together, the data suggested that assessment of apoptosis signaling molecules might have a predictive impact on treatment outcome.     

Iridoid glucosides from Kickxia abhaica D.A. Sutton from Scrophulariaceae

Two iridoid glucosides namely; 6-acetylantirrinoside (1), 6'-O-p-hydroxybenzoylantirrinoside (2) were isolated from the aerial parts of Kickxia abhaica. Beside that, three known iridoid glucosides, antirrinoside (3), antirride (4) and mussaenosidic acid (5), one flavone glycoside (6) and a hexitol, d-mannitol (7) were isolated. The structures of the iridoid glucosides 1-2 were established by 1D and 2D NMR spectral data, including COSY, HMQC and HMBC experiments, as well as HRMS.     

Elevation‐richness pattern of vascular plants in wadis of the arid mountain Gebel Elba,Egypt

Mountains provide a unique opportunity to study drivers of species richness across relatively short elevation gradients. However, few studies have reported elevational patterns for arid mountains. We studied elevation‐richness pattern along an elevational gradient at the arid mountain Gebel Elba, south‐east of Egypt, expecting a unimodal richness pattern. We sampled 133 vegetation plots (10 × 10 m) in four wadis along an elevational gradient from 130 to 680 m which represents the transition from desert to mountain wadi systems. We used generalised additive models to describe the relationship between elevation and plant species richness. We found a strong increase in species richness and Shannon diversity at low elevations followed by a plateau at mid‐ to high elevations. When we analysed each tributary as a single gradient, no pattern was found. The analysed elevational gradient seems to be a major stress gradient in terms of temperature and water availability, exhibiting a trend of increasing species richness that changes to a plateau pattern; a pattern rarely observed for wadi systems in arid mountains. We discuss the observed pattern with the climatic stress hypothesis and the environmental heterogeneity hypothesis as possible explanations for the pattern.