Leishmania donovani infection differentially regulates small G‐proteins

Leishmania is a protozoan parasite that resides and replicates in macrophages and causes leishmaniasis. The parasite alters the signaling cascade in host macrophages and evades the host machinery. Small G‐proteins are GTPases, grouped in 5 different families that play a crucial role in the regulation of cell proliferation, cell survival, apoptosis, intracellular trafficking, and transport. In particular, the Ras family of small G‐proteins has been identified to play a significant role in the cellular functions mentioned before. Here, we studied the differential expression of the most important small G‐proteins during Leishmania infection. We found major changes in the expression of different isoforms of Ras, mainly in N‐Ras. We observed that Leishmania donovani infection led to enhanced N‐Ras expression, whereas it inhibited K‐Ras and H‐Ras expression. Furthermore, an active N‐Ras pull‐down assay showed enhanced N‐Ras activity. L donovani infection also increased extracellular signal–regulated kinase 1/2 phosphorylation and simultaneously decreased p38 phosphorylation. In contrast, pharmacological inhibition of Ras led to reduction in the phosphorylation of extracellular signal–regulated kinase 1/2 and enhanced the phosphorylation of p38 in Leishmania‐infected cells, which could lead to increased interleukin‐12 expression and decreased interleukin‐10 expression. Indeed, farnesylthiosalicyclic acid (a Ras inhibitor), when used at the effective level in L donovani–infected macrophages, reduced amastigotes in the host macrophages. Thus, upregulated N‐Ras expression during L donovani infection could be a novel immune evasion strategy of Leishmania and would be a potential target for antileishmanial immunotherapy.     

Olfactory behavior and response of household ants (Hymenoptera) to different types of coffee odor: A coffee-based bait development prospect

Odor sensation is a sensory modality of considerable significance in the foraging behavior and interactional organization of ants. In the food bait technology, smell is the basis of attraction, which, in turn, is the line of bait use and a key parameter for judging efficacy. Yet, the currently available baits possess low attractiveness to many ant pests. Hence, strategies to produce ant bait with increased attractiveness are needed. Despite evidence that coffee has a diverse aroma complex that affects the behavior of honey bees and ants, its attraction to house-invading ants has yet to be investigated. In a series of Y-tube olfactometer bioassays, we examined the behavioral responses of Tapinoma indicum (TI), Monomorium pharaonis (MP) and Solenopsis geminata (SG) to various coffee-induced odor stimuli, comprised of extracts from Arabica, Robusta and Liberica. All coffee extracts showed an influence on the behavior of TI, MP and SG workers, with Arabica showed the most significant influence to the tested ants. The workers of TI, MP and SG were more attracted to the odor of 0.01% Arabica extract (ONE), in comparison with 0.05% Arabica extract (TWO) or 0.10% Arabica extract (THREE). Arabica extract mixed with sugar (S) elicited a significant attraction from workers of all three species in a balanced competition with either unsweetened Arabica extract or water. These results indicated that coffee, particularly Arabica, was attractive to the foragers of TI, MP and SG, thus, the use of coffee as a novel stimulus agent seems plausible in ant bait development.     

Biology of Anagrus atomus (Hymenoptera: Mymaridae), an egg parasitoid of the grape leafhopper Arboridia kermanshah (Homoptera: Cicadellidae)

Biology, morphology and oviposition behavior of Anagrus atomus (Linnaeus), an egg parasitoid of the grape leafhopper Arboridia kermanshah Dlabola in Isfahan, Iran, were investigated. Adults were smaller than those so far reported from other regions. Females continuously drummed on plant surfaces with their antennae to search for host eggs. Parasitoid eggs hatched 2–3 days after oviposition, and A. atomus had two larval instars. First instar larvae were sacciform and immobile. Second instar larvae appeared 4 days after oviposition and were very active, and doubled their body length. The prepupal and pupal stages lasted for 1 and 5–6 days, respectively. Adult emergence began 16 days after oviposition, and peaked on day 17.     

Model compounds for microbial iron-transport compounds. Part V. Substituent effects in the catechol/FeCl3 system

Titration data are reported for a number of substituted catechol molecules with ferric chloride. The data are interpreted in terms of the complexes formed and their stabilities. The pH's at which one complex transforms to another have been shown to have a linear relationship to modified Hammett substituent constants. It is demonstrated that this approach can be used to forecast approximate stabilities of complexes formed with iron, if the Hammett substituent constant of the ligand is known.     

Bacillus amyloliquefaciens BSL16 improves phytoremediation potential of Solanum lycopersicum during copper stress

Current study aimed at exploring the diversity of bacterial endophytes with Boswellia sacra and their role in copper (Cu) stress to tomato plants. Bacterial endophytes were belonged to Bacillus, Rhizobium and Paenibacillus, which were screened against Cu (0–10?mM) stress to dwarf and normal rice seeds. Among strains, Bacillus amyloliquefaciens BSL16 showed significantly higher bioremediation potential by accumulating high Cu and promoting growth of rice seeds. B. amyloliquefaciens BSL16 significantly increased growth of tomato plants during 2.5?mM Cu stress. Active colonization of BSL16 reduced the accumulation of Cu in leaf, shoot, and root, and in parallel up-regulated total protein contents in leaf and stem. Glutathione peroxidase and reduced glutathione contents were significantly higher and lipid peroxidation was lower in endophyte-treated tomato plants as compared to Cu treatment. The current results conclude that application of metal bio-accumulating bacteria can help in improving the plant growth of tomato plants during Cu stress.     

Linkage mapping of the locus responsible for congenital multiple ocular defects in cattle on bovine Chromosome 18

Congenital multiple ocular defects (MOD) in Japanese black cattle is a hereditary ocular disorder with an autosomal recessive manner of inheritance, showing developmental defects of the lens, retina, and iris, persistent embryonic eye vascularization, and microphthalmia. In the present study, we mapped the locus responsible for the disorder by linkage analysis using 240 microsatellite markers covering the entire bovine genome and an inbred pedigree obtained from commercial herds. The linkage analysis demonstrated a significant linkage between the disorder locus and markers on the proximal region of bovine Chromosome (BTA) 18 with the maximum LOD score of 5.1. Homozygosity mapping using the haplotype of the linked markers further refined the critical region. The results revealed the localization of the locus responsible for MOD in an approximately 6.6-cM region of BTA18. Comparison of published linkage and radiation hybrid (RH) maps of BTA18 with its evolutionary ortholog, human Chromosome (HSA) 16, revealed several potential candidate genes for the disorder including the MAF and FOXC2 genes.     

Relationships between soil seed bank,vegetation and soil fertility along an urbanisation gradient

Questions: How does urbanisation influence soil mineral nitrogen stocks (nitrate and ammonium stocks) and what are the consequences of these modifications on the functional diversity of the herbaceous vegetation (vascular plants) and the seed bank? Location: Nine study sites were located on an urbanisation gradient in the city of Rennes, France. Methods: Three urbanisation levels were defined: urban areas (high grey/green ratio), suburban (medium grey/green ratio) and periurban (low grey/green ratio). For each urbanisation level, nitrates and ammonium stocks were quantified; the herbaceous vegetation was surveyed as well as the soil seed bank (using the seedling emergence method). Results: Nitrate concentration increased with urbanisation (the nitrate level in urban plots was twice the concentration in periurban ones) whereas the ammonium level was higher in periurban areas than in urban areas. In urban plots, the vegetation and the seed bank were more nitrophilous, whereas the nitrogen requirement was lower for periurban species. The relationship between the seed bank and the above‐ground vegetation was not significant. Conclusions: The higher nitrate concentration in the urban area appeared to be related to higher concentrations of atmospheric pollutants found in this area and lower ammonium levels may be related to the higher temperature in urban areas (leading to higher nitrification rates). The shift in the composition of the seed bank and vegetation appeared to be a consequence of higher nitrate stocks. The dissimilarity between the seed bank and vegetation may be caused by enhanced emergence of nitrophilous species in urban areas.