Winter wheat (Triticum aestivum) response to Barley yellow dwarf virus at various nitrogen application rates in the presence and absence of its aphid vector,Rhopalosiphum padi

Barley yellow dwarf (BYD) is one of the most common diseases of cereal crops, caused by the phloem‐limited, cereal aphid‐borne Barley yellow dwarf virus (BYDV) (Luteoviridae). Delayed planting and controlling aphid vector numbers with insecticides have been the primary approaches to manage BYD. There is limited research on nitrogen (N) application effects on plant growth, N status, and water use in the BYDV pathosystem in the absence of aphid control. Such information will be essential in developing a post‐infection management plan for BYDV‐infected cereals. Through a greenhouse study, we assessed whether manipulation of N supply to BYDV‐infected winter wheat, Triticum aestivum L. (Poaceae), in the presence or absence of the aphid vector Rhopalosiphum padi L. (Hemiptera: Aphididae), could improve N and/or water uptake, and subsequently promote plant growth. Similar responses of shoot biomass and of water and N use efficiencies to various N application rates were observed in both BYDV‐infected and non‐infected plants, suggesting that winter wheat plants with only BYDV infection may be capable of outgrowing infection by the virus. Plants, which simultaneously hosted aphids and BYDV, suffered more severe symptoms and possessed higher virus loads than those infected with BYDV only. Moreover, in plants hosting both BYDV and aphids, aphid pressure was positively associated with N concentration within plant tissue, suggesting that N application and N concentration within foliar tissue may alter BYDV replication indirectly through their influence on aphid reproduction. Even though shoot biomass, tissue N concentration, and water use efficiency increased in response to increased N application, decision‐making on N fertilization to plants hosting both BYDV and aphids should take into consideration the potential of aphid outbreak and/or the possibility of reduced plant resilience to environmental stresses due to decreased root growth.     

Point mutations abolishing the mannose-binding capability of boar spermadhesin AQN-1

The mannose-binding capability of recombinant wild-type boar spermadhesin AQN-1 and of its site-directed mutants in the highly-conserved region around of the single glycosylation site (asparagine 50) of some spermadhesins, where the carbohydrate binding site has been proposed to be located, was checked using a solid-phase assay and a biotinylated mannose ligand. Substitution of glycine 54 by amino acids bearing an unipolar side chain did not cause significant decrease in the mannose-binding activity. However, amino acids with uncharged polar side chains or having a charged polar side chain abolished the binding of biotinylated mannose to the corresponding AQN-1 mutants. The results suggest that the higher surface accessibility of amino acids possessing polar side chains compared to those bearing nonpolar groups may sterically interfere with monosaccharide binding. The location of the mannose-binding site in AQN-1 appears to be topologically conserved in other heparin-binding boar spermadhesins, i.e., AQN-3 and AWN, but departs from the location of the mannose-6-phosphate-recognition site of PSP-II. This indicates that different spermadhesin molecules have evolved non-equivalent carbohydrate-binding capabilities, which may underlie their distinct patterns of biological activities.     

Function of the mammalian oviductal sperm reservoir.

Sperm are stored in the isthmic region of the oviduct under conditions that maintain sperm viability and suppress motility. This region is also the site in which essential steps of the capacitation process are coordinated with the appearance of the ovulated egg. The influx of Ca(2+) and phosphorylation of sperm proteins are features of the ongoing capacitation process. Using a cell-culture system of oviductal epithelial cells, it was found that sperm bound to the epithelial cells showed a reduced Ca(2+) uptake and almost no tyrosine phosphorylation as shown by indirect immunofluorescence. Furthermore, sperm viability, measured as membrane integrity with propidium iodide, is significantly prolonged as compared to sperm in suspension. The formation of the sperm reservoir appears to be mediated by carbohydrate-protein interaction. In the pig, it has been found that mannosyl-oligosaccharides exposed by the epithelial cells are high-affinity ligands for sperm-associated lectins. Ovalbumin and mannopentaose are effective inhibitors of sperm binding to explants of oviductal epithelium. Spermadhesins, a new class of animal lectins and the major secretory products of the porcine seminal vesicle, associate with the sperm surface at ejaculation and are candidate molecules for the receptors of the epithelial carbohydrates.     

Carbohydrate-based interactions of oviductal sperm reservoir formation-studies in the pig.

Competitive inhibition of sperm to explants of the oviductal epithelium was used to study the complementary receptor system that may be involved in the establishment of the oviductal sperm reservoir in the pig. Sperm binding to the oviductal explants is expressed as Binding Index (BI = sperm cells/0.01 mm(2)). From a set of glycoproteins with known oligosaccharide structures, only asialofetuin and ovalbumin showed inhibitory activity, indicating that ovalbumin may block high affinity binding sites (IC(50) congruent with 1.3 microM) and asialofetuin low affinity sites (IC(50) congruent with 18 microM) of the complementary receptor systems, whereas fetuin carrying terminal sialic acid has no effect. Ovalbumin glycopeptides were isolated by Con A affinity chromatography and reverse-phase HPLC following tryptic digestion. Glycopeptides and enzymatically released glycans were analyzed by MS, and were shown to represent preferentially the two high mannose type glycans (Man)(5)(GlcNAc)(2) and (Man)(6)(GlcNAc)(2), and as a minor component the hybrid type glycan (Hex)(4)(GlcNAc)(5). Glycopeptides (84% inhibition) and glycans (81% inhibition) significantly reduced sperm-oviduct binding at a concentration of 3 microM, whereas the deglycosylated peptides showed no inhibitory activity. Mannopentaose (IC(50) congruent with 0.8 microM) representing the oligomannose residue of the high mannose glycans of ovalbumin was as effective as ovalbumin. These data indicate that the carbohydrate-based mechanisms underlying the formation of the oviductal sperm reservoir in the pig is the result of the concerted action of at least the high-affinity binding sites for oligomannose or nonreducing terminal mannose residues and low-affinity binding of galactose.     

Expression analysis of selected miR-206 targets from the transforming growth factor-β signaling pathway in breast cancer

Breast cancer as a molecularly heterogeneous malignancy is associated with dysregulation of several signaling pathways, including transforming growth factor-β (TGF-β) signaling. On the other hand, several recent studies have demonstrated the role of microRNAs (miRNAs) in breast cancer pathogenesis. In the current study, we performed a computerized search to find miR-206 target genes that are functionally linked to the TGF-β signaling pathway. We selected LEF1, Smad2, and Snail2 genes to assess their expression in 65 breast cancer samples and their adjacent noncancerous tissues (ANCTs) in correlation with expression levels of miR-206 as well as clinicopathological characteristics of patients. miR-206 was significantly downregulated in (Estrogen receptor) ER-positive breast cancer samples compared with their corresponding ANCTs. Association analysis between expression levels of genes and demographic features of patients showed significant association between expressions of SMAD2 and LEF1 genes and body mass index ( P values of 0.03 and 0.02, respectively). miR-206 low-expression levels were associated with TNM stage, mitotic rate, and lymph node involvement ( P values of 0.02, 0.01, and 0.01 respectively). In addition, SMAD2 high-expression levels were associated with HER2 status ( P = 0.02). Consequently, our data highlight the role of TGF-β signaling dysregulation in the pathogenesis of breast cancer and warrant further evaluation of miRNAs and messenger RNA coding genes in this pathway to facilitate detection of cancer biomarkers and therapeutic targets.     

Terahertz Response of ZnS/Ge and ZnO/Ge Nanostructured Composites

We present a new set of nanostructured composites which can exhibit a phenomenon known as surface plasmon resonance in a broad frequency range from the deep infrared to the terahertz region. The structures are composites of two different kinds of non-overlapping spheres. These spheres are made from a high refractive index nonplasmonic material and a Drude-like plasmonic material. Our results are explained in the context of the extended Maxwell–Garnett theory. The effective permittivity and refractive index of zinc sulfide/Ge and zinc oxide/Ge composites have been calculated over terahertz frequencies.     

Renalase rs10887800 polymorphism is associated with severe pre-eclampsia in southeast Iranian women

Evidence has shown that pre-eclampsia (PE) is associated with an increased level of catecholamines. Renalase is a catecholamine-metabolizing enzyme, which contributes to the occurrence of hypertension. In the current study, we aimed to assess the relation between two renalase gene ( RNLS) polymorphisms, including rs2576178 at the 5′-flanking region and rs10887800 at intron 6, near the exon/intron border and PE susceptibility. In this case-control study, 179 women with PE and 202 normotensive pregnant women were genotyped for RNLS rs2576178 and rs10887800 polymorphisms by the polymerase chain reaction-restriction fragment length polymorphism method. There was no association between RNLS rs10887800 and rs2576178 polymorphisms and PE, neither in the dominant nor in the recessive model. Although there was no association between RNLS rs10887800 polymorphism and mild PE, this polymorphism was associated with 2.2-fold higher risk of severe PE in the recessive model (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.2-4.4; P = 0.01) but not in the dominant model. The RNLS rs2576178 and rs10887800 polymorphisms were not associated with PE severity. The RNLS rs10887800 and rs2576178 GG/GG combined genotypes were associated with 8.4- and 16.7-fold higher risk of PE and severe PE, respectively (OR, 8.4; 95% CI, 1-71.1; P = 0.048 and OR, 16.7; 95% CI, 1.6-167; P = 0.018). Also, the G-G haplotype was associated with 1.7-fold risk of PE and mild PE (OR, 1.7; 95% CI, 1.1-2.4; P = 0.009 and OR, 1.7; 95% CI, 1.1-2.5; P = 0.02). The RNLS rs10887800 polymorphism was associated with severe PE. The RNLS rs10887800 and rs2576178 GG/GG combined genotypes and G-G haplotype were associated with higher risk of PE.     

In Vitro Influences of TiO2 Nanoparticles on Barley (Hordeum vulgare L.) Tissue Culture

In the last decades, extensive research on the effects of nano-TiO₂ on plant systems and different microorganisms has confirmed its photocatalytic and antimicrobial activity. However, there is no report on its application in plant cell and tissue culture as well as its role in eliminating contaminating microorganisms in tissue culture. In this work, barley mature embryos were cultured in Murashige and Skoog medium with four concentrations (0, 10, 30, 60???g/ml) of TiO₂ suspension in four repetitions. Quantitative and qualitative characteristics of calli were analyzed after each subculture. Data analysis for calli number in the first culture and callus size in all three cultures showed that the effect of treatment was significant at p?>?0.95. As a result, quantitative features such as callus color, shape, embryogenesis, etc. were completely similar in both control and TiO₂ nanoparticle treatments; there is no doubt that TiO₂ nanoparticles could dramatically increase callugenesis and the size of calli. As well, TiO₂ nanoparticles are effective bactericides with an aseptic effect, causing no negative change in the quality of the callus. It is necessary to do more complementary works to identify mechanisms involved for the increased calli size and embryogenesis of explants in darkness.     

The effect of sea anemone (H. magnifica) venom on two human breast cancer lines: death by apoptosis

Venom from the sea anemone, Heteractis magnifica, has multiple biological effects including, cytotoxic, cytolytic and hemolytic activities. In this study, cytotoxicity induced by H. magnifica venom was investigated using the crystal violet assay on human breast cancer T47D and MCF7 cell lines and normal human breast 184B5 cell line. Apoptosis was also assayed via Annexin V-flourescein isothiocyanate and propidium iodide (PI) staining followed by flow cytometric analysis. Cell cycle progression and mitochondria membrane potential were studied via flow cytometry following PI and JC-1 staining respectively. H. magnifica venom induced significant reductions in viable cell numbers and increases in apoptosis in T47D and MCF7 in dose-dependent manners. A significant apoptosis-related increase in the sub G1 peak of the cell cycle in both breast cancer cell lines was also observed. Moreover, treatment by venom cleaved caspase-8, caspase-9, and activated caspase-3. Overall, H. magnifica venom was highly cytotoxic to T47D and MCF7 human breast cancer cells, and the phenomenon could be the killing phenomenon via the death receptor-mediated and the mitochondria-mediated apoptotic pathways. Consequently, H. magnifica venom has potential for the development of a breast cancer therapeutic.