Identification of an alpha3-fucosyltransferase and a novel alpha2- fucosyltransferase activity in cercariae of the schistosome Trichobilharzia ocellata: biosynthesis of the Fucalpha1-->2Fucalpha1-- >3[Gal(NAc)beta1-->4]GlcNAc sequence

Fucose is a major constituent of the protein- and lipid-linked glycans of the various life-cycle stages of schistosomes. These fucosylated glycans are highly antigenic and seem to play a role in the pathology of schistosomiasis. In this article we describe the identification and characterization of two fucosyltransferases (FucTs) in cercariae of the avian schistosome Trichobilharzia ocellata, a GDP-Fuc:[Galbeta1-- >4]GlcNAcbeta-R alpha1-->3-FucT and a novel GDP-Fuc:Fucalpha-R alpha1-- >2-FucT. Triton X-100 extracts of cercariae were assayed for FucT activity using a variety of acceptor substrates. Type 1 chain (Galbeta1- ->3GlcNAc) based compounds were poor acceptors, whereas those based on a type 2 chain (Galbeta1-->4GlcNAc), whether alpha2'-fucosylated, alpha3'-sialylated, or unsubstituted, and whether present as oligosaccharide or contained in a glycopeptide or glycoprotein, all served as acceptor substrates. In this respect the schistosomal alpha3- FucT resembles human FucT V and VI rather than other known FucTs. N- ethylmaleimide, an inhibitor of several human FucTs, had no effect on the activity of the schistosomal alpha3-FucT, whereas GDP-beta-S was strongly inhibitory. Large scale incubations were carried out with Galbeta1-->4GlcNAc, GalNAcbeta1-->4GlcNAcbeta-O -(CH2)8COOCH3 and Fucalpha1-->3GlcNAcbeta1-->2Man as acceptor substrates and the products of the incubations were isolated using a sequence of chromatographic techniques. By methylation analysis and 2D-TOCSY and ROESY1H-NMR spectroscopy the products formed were shown to be Galbeta1-- >4[Fucalpha1-->2Fucalpha1-->3]GlcNAc, GalNAcbeta1-->4[Fucalpha1-- >2Fucalpha1-->3]GlcNAcbe ta-O-(CH2)8COOCH3, and Fucalpha1-->2Fucalpha1-- >3GlcNAcbeta1-->2Man, respectively. It is concluded that the alpha2- FucT and alpha3-FucT are involved in the biosynthesis of the (oligomeric) Lewisx sequences and the Fucalpha1-->2Fucalpha1-->3GlcNAc structural element that have been described on schistosomal glycoconjugates.      

Identification of Toxigenic Fusarium Species using PCR Assays

Isolates of the toxigenic cereal pathogens Fusarium culmorum, Fusarium graminearum, Fusarium crookwellense and Fusarium avenaceum, from Poland (48 isolates) and 12 from England, New Zealand, Italy and Canada, were examined using random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR), sequence-characterized amplified regions (SCARs), morphology and mycotoxin production under laboratory conditions. Their DNA products were compared by RAPD-PCR, which showed species-specific bands and the greatest diversity among isolates of F. avenaceum. PCR using three 20-mer-primer-pairs that are reported to be useful for identification of F. culmorum and F. graminearum group 2 confirmed their species-specificity. The same species-specific PCR product was observed in isolates of both nivalenol and deoxynivalenol chemotypes of F. culmorum or F. graminearum. A clear relationship was found between morphological and species-specific PCR identification of F. culmorum and F. graminearum isolates. However, F. avenaceum can be confused when using primers FA-ITS F/R (SCAR 2-14) with Fusarium tricinctum because the same band 272 bp appears in the gel, in both species probes.     

Pairwise Comparisons in Each of Several Groups with Heterogenous Group Variances

Pairwise comparison procedures are frequently applied to analyze experimental results. In particular, practitioners in the area of medical researches often encounter situations which require these statistical techniques to compare various treatments. In this article, we focus on pairwise comparison procedures in a two‐factor design, where comparisons of one factor are made simultaneously for each level of another factor. For example, several new drugs to treat a certain cancer are being compared for both male and female patients. Previous research efforts were mainly devoted to models with homogeneous variances. The current paper is to address more common scenario where group variances are heterogeneous.     

Blastocystis hominis: A simplified, high-efficiency method for clonal growth on solid agar

Colony growth of protozoan parasites in agar can be useful for axenization, cloning, and viability studies. This is usually achieved with the pour plate method, for which the parasite colonies are situated within the agar. This technique has been described for Giardia intestinalis, Trichomonas vaginalis, and Entamoeba and Blastocystis species. Extracting such colonies can be laborious. It would be especially useful if parasites could be grown on agar as colonies. These colonies, being exposed on the agar surface, could be conveniently isolated for further investigation. In this study, we report the successful culture of B. hominis cells as colonies on solid agar. Colonies were enumerated and the efficiency of plating was determined. It was observed that B. hominis could be easily cultured on agar as clones. The colonies were dome-shaped and mucoid and could grow to 3 mm in diameter. Flow cytometric analyses revealed that parasite colonies remained viable for up to 2 weeks. Viable colonies were conveniently expanded in liquid or solid media. Scanning electron microscopy revealed that each colony consists of two regions; a dome-shaped, central core region and a flattened, peripheral region. Older colonies possessed numerous strand-like surface coat projections. This study provides the first report of clonal growth of B. hominis on agar and a simple, effective method for cloning and expansion of B. hominis cells.     

云南澜沧县陆稻品种资源多样性和原生境保护

云南澜沧县不仅存在丰富的陆稻品种多样性和形态多样性,而且也存在陆稻生长环境和栽种管理方法的多样性,即山地民族在陆稻栽种方面的土著知识（indigenous knowledge,IK）多样性,讨论了由传统的刀耕火种生产制度过渡到现代固耕生产方式对陆稻生产及品种资源保存和保护的影响。提出了陆稻资源多样性保护的建议。     

Green synthesis and characterization of selenium nanoparticles and its augmented cytotoxicity with doxorubicin on cancer cells

Green synthesis of selenium nanoparticles (SeNPs) was achieved by a simple biological procedure using the reducing power of fenugreek seed extract. This method is capable of producing SeNPs in a size range of about 50–150 nm, under ambient conditions. The synthesized nanoparticles can be separated easily from the aqueous sols by a high-speed centrifuge. These selenium nanoparticles were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and elemental analysis by X-ray fluorescence spectrometer (XRF). Nanocrystalline SeNPs were obtained without post-annealing treatment. FTIR spectrum confirms the presence of various functional groups in the plant extract, which may possibly influence the reduction process and stabilization of nanoparticles. The cytotoxicity of SeNPs was assayed against human breast-cancer cells (MCF-7). It was found that SeNPs are able to inhibit the cell growth by dose-dependent manner. In addition, combination of SeNPs and doxorubicin shows better anticancer effect than individual treatments.     

Proteomics identification of ITGB3 as a key regulator in reactive oxygen species-induced migration and invasion of colorectal cancer cells

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in males and second in females worldwide. Unfortunately 40-50% of patients already have metastatic disease at presentation when prognosis is poor with a 5-year survival of <10%. Reactive oxygen species (ROS) have been proposed to play a crucial role in tumor metastasis. We now show that higher levels of ROS accumulation are found in a colorectal cancer-derived metastatic cell line (SW620) compared with a cell line (SW480) derived from the primary lesion from the same patient. In addition, ROS accumulation can affect both the migratory and invasive capacity of SW480 and SW620 cells. To explore the molecular mechanism underlying ROS-induced migration and invasion in CRC, we have compared protein expression patterns between SW480 and SW620 cells using a two-dimensional electrophoresis-based proteomics strategy. A total of 63 altered proteins were identified from tandem MS analysis. Cluster analysis revealed dysregulated expression of multiple redox regulative or ROS responsive proteins, implicating their functional roles in colorectal cancer metastasis. Molecular and pathological validation demonstrated that altered expression of PGAM1, GRB2, DJ-1, ITGB3, SOD-1, and STMN1 was closely correlated with the metastatic potential of CRC. Functional studies showed that ROS markedly up-regulated expression of ITGB3, which in turn promoted an aggressive phenotype in SW480 cells, with concomitant up-regulated expression of STMN1. In contrast, knockdown of ITGB3 expression could mitigate the migratory and invasive potential of SW620 or H(2)O(2)-treated SW480 cells, accompanied by down-regulated expression of STMN1. The function of ITGB3 was dependent on the surface expression of integrin αvβ3 heterodimer. Furthermore, STMN1 expression and the PI3K-Akt-mTOR pathway were found to be involved in ROS-induced and ITGB3-mediated migration and invasion of colorectal cancer cells. Taken together, these studies suggest that ITGB3 plays an important role in ROS-induced migration and invasion in CRC.     

Plasticity in flower size as an adaptation to variation in pollinator specificity

1. Mutualisms, including plant-pollinator interactions, are an important component of ecosystems. 2. Plants can avoid the costs of variation in pollinator benefit by maintaining specificity. 3. We hypothesise a novel mechanism to ensure specificity, which takes advantage of the cognitive abilities of specific pollinators to exclude non-specific flower visitors. 4. Inflorescences of the tropical vine genus Psiguria produce flowers at regular intervals, with subsequent flowers smaller than predecessors. 5. The principle pollinators, Heliconius spp., possess an excellent spatial memory. 6. Therefore, decreasing flower size may ensure specific pollination: once Heliconius individuals have learnt the location of an inflorescence they will return, but inconspicuous flowers should reduce visits by non-specific pollinators with poorer spatial memories. 7. We tested the predictions of this hypothesis with field experiments in Panama. We confirmed that flowers on inflorescences are smaller than their predecessors. 8. Paired experiments showed that larger flowers attracted more pollinators and that the presence of an initial large flower increased subsequent visitation by Heliconius spp. to small flowers, indicating learning behaviour. 9. These results suggest that learning behaviour and decreasing flower size maintain visits from specific pollinators while reducing those from non-specific pollinators. We propose this as a novel mechanism for promoting pollinator specificity and discuss its ecological significance.     

Transcriptome‐based target‐enrichment baits for stony corals (Cnidaria: Anthozoa: Scleractinia)

Despite the ecological and economic significance of stony corals (Scleractinia), a robust understanding of their phylogeny remains elusive due to patchy taxonomic and genetic sampling, as well as the limited availability of informative markers. To increase the number of genetic loci available for phylogenomic analyses in Scleractinia, we designed 15,919 DNA enrichment baits targeting 605 orthogroups (mean 565 ± SD 366 bp) over 1,139 exon regions. A further 236 and 62 barcoding baits were designed for COI and histone H3 genes respectively for quality and contamination checks. Hybrid capture using these baits was performed on 18 coral species spanning the presently understood scleractinian phylogeny, with two corallimorpharians as outgroup. On average, 74% of all loci targeted were successfully captured for each species. Barcoding baits were matched unambiguously to their respective samples and revealed low levels of cross‐contamination in accordance with expectation. We put the data through a series of stringent filtering steps to ensure only scleractinian and phylogenetically informative loci were retained, and the final probe set comprised 13,479 baits, targeting 452 loci (mean 531 ± SD 307 bp) across 865 exon regions. Maximum likelihood, Bayesian and species tree analyses recovered maximally supported, topologically congruent trees consistent with previous phylogenomic reconstructions. The phylogenomic method presented here allows for consistent capture of orthologous loci among divergent coral taxa, facilitating the pooling of data from different studies and increasing the phylogenetic sampling of scleractinians in the future.