Cellular origin and development of secondary somatic embryos in Oncidium leaf cultures

We report here for the first time that fully differentiated stomatal guard cells have the ability to form directly secondary somatic embryos. Histological and scanning electron microscopy studies reveal that the stomata are formed on primary embryos of both Oncidium cultivars Gower Ramsey and Sweet Sugar. Secondary embryogenesis from these guard cells could be induced by several plant growth regulators (PGRs), including N⁶-benzyladenine, kinetin, thidiazuron, 1-aminocyclopropane-1carboxylic acid (ACC), ancymidol and 2,3,5-triiodobenzoic acid. When compared with other PGRs, ACC at concentration 1 mg dm⁻³ resulted in highest number of secondary embryos that were derived from guard cells. The present communication provides a model system for studying factors and mechanism affecting totipotency or embryogenetic capacity of guard cells.     

Microbial Populations in Naked Neck Chicken Ceca Raised on Pasture Flock Fed with Commercial Yeast Cell Wall Prebiotics via an Illumina MiSeq Platform

Prebiotics are non-digestible carbohydrate dietary supplements that selectively stimulate the growth of one or more beneficial bacteria in the gastrointestinal tract of the host. These bacteria can inhibit colonization of pathogenic bacteria by producing antimicrobial substances such as short chain fatty acids (SCFAs) and competing for niches with pathogens within the gut. Pasture flock chickens are generally raised outdoors with fresh grass, sunlight and air, which represents different environmental growth conditions compared to conventionally raised chickens. The purpose of this study was to evaluate the difference in microbial populations from naked neck chicken ceca fed with commercial prebiotics derived from brewer’s yeast cell wall via an Illumina MiSeq platform. A total of 147 day-of-hatch naked neck chickens were distributed into 3 groups consisted of 1) C: control (no prebiotic), 2) T1: Biolex^® MB40 with 0.2%, and 3) T2: Leiber^® ExCel with 0.2%, consistently supplemented prebiotics during the experimental period. At 8 weeks, a total of 15 birds from each group were randomly selected and ceca removed for DNA extraction. The Illumina Miseq platform based on V4 region of 16S rRNA gene was applied for microbiome analysis. Both treatments exhibited limited impact on the microbial populations at the phylum level, with no significant differences in the OTU number of Bacteroidetes among groups and an increase of Proteobacteria OTUs for the T1 (Biolex^® MB40) group. In addition there was a significant increase of genus Faecalibacterium OTU, phylum Firmicutes. According to the development of next generation sequencing (NGS), microbiome analysis based on 16S rRNA gene proved to be informative on the prebiotic impact on poultry gut microbiota in pasture-raised naked neck birds.     

The historical evolutionary development of Hemerocallis middendorfii (Hemerocallidaceae) revealed by non-coding regions in chloroplast DNA

A procedure in which combined molecular phylogeographical analyses among populations of Hemerocallis middendorfii (Hemerocallidaceae, Asparagales) were applied allowed comparisons to be made with the geological history. Information on geographical areas in which synapomorphic mutations occurred was used in molecular phylogeographical analyses for the first time in this study, in addition to molecular maximum-parsimonious analyses and TCS analyses. Nucleotide sequences of the intergenic region between the rbcL and atpB genes and the trnL (UAA) intron in chloroplast DNA were analyzed for 28 Japanese and three Chinese populations of H. middendorfii, 10 populations of closely related species and four outgroup species. The data of the three analyses in general agreed with one another and indicated that the separation of this species had proceeded in conjunction with the geological vicariance or orogeny. Where the synapomorphic mutations occurred, three patterns were recognized. They correlated with the geological history, namely, the age when the Japanese Archipelago and the Continent had joined, when the Sea of Japan was formed, and when there was separation from the Continent and the formation of each of the islands in the Japanese Archipelago. It was suggested that ancestors of H. middendorfii originated at latest 25 million years ago when the Japanese Archipelago and the Continent had joined; that is, before the formation of the Sea of Japan.We are greatly obliged to three anonymous reviewers for their constructive comments.     

Dynamics of a Cytokine Storm

Six volunteers experienced severe inflammatory response during the Phase I clinical trial of a monoclonal antibody that was designed to stimulate a regulatory T cell response. Soon after the trial began, each volunteer experienced a “cytokine storm”, a dramatic increase in cytokine concentrations. The monoclonal antibody, TGN1412, raised serum concentrations of both pro- and anti-inflammatory cytokines το very hiγh values during the first day, while lymphocyte and monocyte concentrations plummeted. Because the subjects were healthy and had no prior indications of immune deficiency, this event provided an unusual opportunity to study the dynamic interactions of cytokines and other measured parameters. Here, the response histories of nine cytokines have been modeled by a set of linear ordinary differential equations. A general search procedure identifies parameters of the model, whose response fits the data well during the five-day measurement period. The eighteenth-order model reveals plausible cause-and-effect relationships among the cytokines, showing how each cytokine induces or inhibits other cytokines. It suggests that perturbations in IL2, IL8, and IL10 have the most significant inductive effect, while IFN-γ and IL12 have the greatest inhibiting effect on other cytokine concentrations. Although TNF-α is a major pro-inflammatory factor, IFN-γ and three other cytokines have faster initial and median response to TGN1412 infusion. Principal-component analysis of the data reveals three clusters of similar cytokine responses: [TNF-α, IL1, IL10], [IFN-γ, IL2, IL4, IL8, and IL12], and [IL6]. IL1, IL6, IL10, and TNF-α have the highest degree of variability in response to uncertain initial conditions, exogenous effects, and parameter estimates. This study illuminates details of a cytokine storm event, and it demonstrates the value of linear modeling for interpreting complex, coupled biological system dynamics from empirical data.