Morpho–physiological responses of Rocket (<Emphasis Type="Italic">Eruca sativa</Emphasis> L.) varieties to sodium sulfate (Na<Subscript>2</Subscript>SO<Subscript>4</Subscript>) stress: an experimental approach

Rocket (Eruca sativa L.) is a medicinal plant that belongs to the Brassicaceae family and was reported to be a tolerant plant under soil salinity as well as high genetic diversity among its varieties. Since morphological and physiological changes to sodium sulfate stress toward this plant have not been investigated yet, the present study was implemented to assess the response of rocket (Eruca sativa L.) varieties to sodium sulfate (Na2SO4) stress as well as the relationship among these traits. Two varieties of rocket plants, the Iranian and Italian ones, were subjected to four salinity (Na₂SO₄) treatments [0 (control), 15, 30 and 60 mM of Na₂SO₄ solution] and three growth stages (49, 65, and 74 days) in factorial experiment with completely randomized design and three replications were considered. Some morphologic traits such as grain yield were measured during the growth period. The results of the analysis of variances between the mentioned variables indicated a significant difference between the varieties in terms of K⁺, Na⁺, Na⁺/K⁺, leaf length, grain yield, organic and mineral matter. The results of correlation and regression of the amounts of K⁺ showed a linear relationship with the grain yield and its variations were not independent from the variations of grain yield. Eventually, it seems that the Italian variety was more tolerant and having better performance in comparison with the Iranian variety, in response to salt stress.     

Plant growth-promoting potential of endophytic bacteria isolated from roots of wild <Emphasis Type="Italic">Dodonaea viscosa</Emphasis> L.

Dodonaea viscosa, a wild and perennial shrub that can tolerate harsh environmental conditions, was used for the isolation of its endophytic bacteria and their potential was explored for the promotion of Canola growth. The bacteria identified through 16S rRNA gene sequencing, belonged to ten different genera namely Inquilinus, Xanthomonas, Pseudomonas, Rhizobium, Brevundimonas, Microbacterium, Bacillus, Streptomyces, Agrococcus and Stenotrophomonas. All the strains produced small amount of IAA (indole acetic acid) in the absence of tryptophan and comparatively more in the presence of tryptophan. All the bacterial strains were positive for ammonia production, cellulase and pectinase activity, but few of them showed phosphate solubilization, siderophore and hydrogen cyanide production. Only three strains showed ACC (1-aminocyclopropane-1-carboxylate) deaminase activity when tested using in-vitro enzyme assay. Members of genera Bacillus, Pseudomonas and Streptomyces showed positive chitinase, protease and antifungal activity against two phytopathogenic fungi Aspergillus niger and Fusarium oxysoprum, while members of Xanthomonas, Pseudomonas and Bacillus showed significant root elongation of Canola which could be related with their positive plant-growth-promoting (PGP) traits. Among the three plant growth promoting Bacillus strains, B. idriensis is never reported before for its PGP activities. These results showed the potential of Dodonaea viscosa endophytic bacteria as PGPBs, which in future can be further explored for their host range/molecular mechanisms.     

Studies on the binding affinity of anticancer drug mitoxantrone to chromatin, DNA and histone proteins

Mitoxantrone is a potent antitumor drug, widely used in the treatment of various cancers. In the present study, we have investigated and compared the affinity of anticancer drug, mitoxantrone, to EDTA-soluble chromatin (SE-chromatin), DNA and histones employing UV/Vis, fluorescence, CD spectroscopy, gel electrophoresis and equilibrium dialysis techniques. The results showed that the interaction of mitoxantrone with SE-chromatin proceeds into compaction/aggregation as revealed by reduction in the absorbencies at 608 and 260 nm (hypochromicity) and disappearance of both histones and DNA on the gels. Mitoxantrone interacts strongly with histone proteins in solution making structural changes in the molecule as shown by CD and fluorescence analysis. The binding isotherms demonstrate a positive cooperative binding pattern for the chromatin- mitoxantrone interaction. It is suggested higher binding affinity of mitoxantrone to chromatin compared to DNA implying that the histone proteins may play an important role in the chromatin- mitoxantrone interaction process.     

THE IMPORTANCE OF MOSQUITO BEHAVIOURAL ADAPTATIONS TO MALARIA CONTROL IN AFRICA

Over the past decade the use of long‐lasting insecticidal nets (LLINs), in combination with improved drug therapies, indoor residual spraying (IRS), and better health infrastructure, has helped reduce malaria in many African countries for the first time in a generation. However, insecticide resistance in the vector is an evolving threat to these gains. We review emerging and historical data on behavioral resistance in response to LLINs and IRS. Overall the current literature suggests behavioral and species changes may be emerging, but the data are sparse and, at times unconvincing. However, preliminary modeling has demonstrated that behavioral resistance could have significant impacts on the effectiveness of malaria control. We propose seven recommendations to improve understanding of resistance in malaria vectors. Determining the public health impact of physiological and behavioral insecticide resistance is an urgent priority if we are to maintain the significant gains made in reducing malaria morbidity and mortality.     

Llama-derived Single Variable Domains (Nanobodies) Directed against Chemokine Receptor CXCR7 Reduce Head and Neck Cancer Cell Growth in Vivo

The chemokine receptor CXCR7, belonging to the membrane-bound G protein-coupled receptor superfamily, is expressed in several tumor types. Inhibition of CXCR7 with either small molecules or small interference (si)RNA has shown promising therapeutic benefits in several tumor models. With the increased interest and effectiveness of biologicals inhibiting membrane-bound receptors we made use of the “Nanobody platform” to target CXCR7. Previously we showed that Nanobodies, i.e. immunoglobulin single variable domains derived from naturally occurring heavy chain-only camelids antibodies, represent new biological tools to efficiently tackle difficult drug targets such as G protein-coupled receptors. In this study we developed and characterized highly selective and potent Nanobodies against CXCR7. Interestingly, the CXCR7-targeting Nanobodies displayed antagonistic properties in contrast with previously reported CXCR7-targeting agents. Several high affinity CXCR7-specific Nanobodies potently inhibited CXCL12-induced β-arrestin2 recruitment in vitro. A wide variety of tumor biopsies was profiled, showing for the first time high expression of CXCR7 in head and neck cancer. Using a patient-derived CXCR7-expressing head and neck cancer xenograft model in nude mice, tumor growth was inhibited by CXCR7-targeting Nanobody therapy. Mechanistically, CXCR7-targeting Nanobodies did not inhibit cell cycle progression but instead reduced secretion of the angiogenic chemokine CXCL1 from head and neck cancer cells in vitro, thus acting here as inverse agonists, and subsequent angiogenesis in vivo. Hence, with this novel class of CXCR7 inhibitors, we further substantiate the therapeutic relevance of targeting CXCR7 in head and neck cancer.     

Comparative evaluation of extraction methods for total proteins from Crocus sativus L. (Saffron)

Broadly speaking proteomic studies are one of the various techniques of utmost importance for understanding complex biological processes that occur under inductive conditions and revealing the multidimensional aspects of Crocus sativus in biological systems. In order to get an insight into the molecular changes and to characterize the variations in protein expression of C. sativus, a detailed proteomic analysis on one-dimensional gel electrophoresis is one of the basic steps to accomplish. We have compared total protein profiles of C. sativus extracted by three different recipes and analyzed on 10% sodium dodecyl sulfate polyacrylamide gels. Gels were subjected to densitometric analysis for further characterization. Among three different protocols NP-40 extraction buffer recipe resulted in the extraction of proteins most efficiently with minimum background and streaking. There was maximum solubilization of proteins with high efficiency. Such a profile can be used for high precision analysis of differential protein expression. This work is an attempt to assist researchers in effective extraction of proteins from C. sativus. As a researcher faces a perplexing array of choices as where to start we describe a method based on our collective analysis of the different protein protocols. This paper presents a method that could be applied at the outset of any proteomic study.     

Early Exposure to Ketamine Impairs Axonal Pruning in Developing Mouse Hippocampus

Mounting evidence suggests that prolonged exposure to general anesthesia (GA) during brain synaptogenesis damages the immature neurons and results in long-term neurocognitive impairments. Importantly, synaptogenesis relies on timely axon pruning to select axons that participate in active neural circuit formation. This process is in part dependent on proper homeostasis of neurotrophic factors, in particular brain-derived neurotrophic factor (BDNF). We set out to examine how GA may modulate axon maintenance and pruning and focused on the role of BDNF. We exposed post-natal day (PND)7 mice to ketamine using a well-established dosing regimen known to induce significant developmental neurotoxicity. We performed morphometric analyses of the infrapyramidal bundle (IPB) since IPB is known to undergo intense developmental modeling and as such is commonly used as a well-established model of in vivo pruning in rodents. When IPB remodeling was followed from PND10 until PND65, we noted a delay in axonal pruning in ketamine-treated animals when compared to controls; this impairment coincided with ketamine-induced downregulation in BDNF protein expression and maturation suggesting two conclusions: a surge in BDNF protein expression “signals” intense IPB pruning in control animals and ketamine-induced downregulation of BDNF synthesis and maturation could contribute to impaired IPB pruning. We conclude that the combined effects on BDNF homeostasis and impaired axon pruning may in part explain ketamine-induced impairment of neuronal circuitry formation.     

Antibacterial evaluation of silver nanoparticles synthesized from lychee peel: individual versus antibiotic conjugated effects

This paper describes the extracellular synthesis of silver nanoparticles from waste part of lychee fruit (peel) and their conjugation with selected antibiotics (amoxicillin, cefixim, and streptomycin). FTIR studies revealed the reduction of metallic silver and stabilization of silver nanoparticles and their conjugates due to the presence of CO (carboxyl), OH (hydroxyl) and CH (alkanes) groups. The size of conjugated nanoparticles varied ranging from 3 to 10 nm as shown by XRD. TEM image revealed the spherical shape of biosynthesized silver nanoparticles. Conjugates of amoxicillin and cefixim showed highest antibacterial activity (147.43 and 107.95%, respectively) against Gram-negative bacteria i.e. Alcaligenes faecalis in comparison with their control counterparts. The highest reduction in MIC was noted against Gram-positive strains i.e. Enterococcus faecium (75%) and Microbacterium oxydans (75%) for amoxicillin conjugates. Anova two factor followed by two-tailed t test showed non-significant results both in case of cell leakage and protein estimation between nanoparticles and conjugates of amoxicillin, cefixime and streptomycin. In case of MDA release, non-significant difference among the test samples against the selected strains. Our study found green-synthesized silver nanoparticles as effective antibacterial bullet against both Gram positive and Gram negative bacteria, but they showed a more promising effect on conjugation with selected antibiotics against Gram negative type.