Limited vegetative compatibility as a cause of somatic recombination in: Trichoderma pseudokoningii.

With the aim of a better characterization of the somatic recombination process in Trichoderma pseudokoningii, a progeny from crossings between T. pseudokoningii strains contrasting for auxotroph markers was characterized by RAPD markers and PFGE (electrophoretic karyotype). Cytological studies of the conidia, conidiogenesis and heterokaryotic colonies were also performed. The genotypes of the majority of the recombinant strains analyzed were similar to only one of the parental strains and the low frequency of polymorphic RAPD bands suggested that the nuclear fusions may not occur into the heterokaryon. In some heterokaryotic regions the existence of intensely staining hyphae might be related to cell death. We proposed that a mechanism of somatic recombination other than parasexuality might occur, being related to limited vegetative compatibility after postfusion events, as described for other Trichoderma species

Agrobacterium-mediated transformation of Guignardia citricarpa: an efficient tool to gene transfer and random mutagenesis.

Guignardia citricarpa is the causal agent of Citrus Black Spot (CBS), an important disease in Citriculture. Due to the expressive value of this activity worldwide, especially in Brazil, understanding more about the functioning of this fungus is of utmost relevance, making possible the elucidation of its infection mechanisms, and providing tools to control CBS. This work describes for the first time an efficient and successful methodology for genetic transformation of G. citricarpa mycelia, which generated transformants expressing the gene encoding for the gfp (green fluorescent protein) and also their interaction with citrus plant. Mycelia of G. citricarpa were transformed via Agrobacterium tumefaciens, which carried the plasmid pFAT-gfp, contains the genes for hygromycin resistance (hph) as well as gfp. The optimization of the agrotransformation protocol was performed testing different conditions (type of membrane; inductor agent concentration [acetosyringonee - AS] and cocultivation time). Results demonstrated that the best condition occurred with the utilization of cellulose?s ester membrane; 200µM of AS and 96 h as cocultivation time. High mitotic stability (82 %) was displayed by transformants using Polymerase Chain Reaction (PCR) technique to confirm the hph gene insertion. In addition, the presence of gfp was observed inside mycelia by epifluorescence optical microscopy. This technique easy visualization of the behaviour of the pathogen interacting with the plant for the first time, allowing future studies on the pathogenesis of this fungus. The establishment of a transformation method for G. citricarpa opens a range of possibilities and facilitates the study of insertional mutagenesis and genetic knockouts, in order to identify the most important genes involved in the pathogenesis mechanisms and plant-pathogen interaction

PIBF+ extracellular vesicles from mouse embryos affect IL-10 production by CD8+ cells

Earlier evidence suggests, that the embryo signals to the maternal immune system. Extracellular vesicles (EVs) are produced by all types of cells, and because they transport different kinds of molecules from one cell to the other, they can be considered as means of intercellular communication. The aim of this work was to test, whether the embryo is able to produce sufficient amounts of EVs to alter the function of peripheral lymphocytes. Embryo-derived EVs were identified by their Annexin V biding capacity, and sensitivity to Triton X dependent lysis, using flow cytometry. Transmission electron microscopy was used to detect EVs at the implantation site. Progesterone-induced blocking factor (PIBF) expression in embryo-derived EVs was demonstrated with immuno-electron microscopy. The % of IL-10 + murine lymphocytes was determined by flow cytometry. EVs were present in embryo culture media, but not in empty media. Mouse embryo-derived EVs adhere to the surface of both CD4+ and CD8+ murine peripheral T lymphocytes, partly, via phosphatidylserine binding. The number of IL-10+ murine peripheral CD8+ cells increases in the presence of embryo-derived EVS, and this effect is counteracted by pre-treatment of EVs with an anti-PIBF antibody, suggesting that the embryo communicates with the maternal immune system via EVs

Expanding Stereochemical and Skeletal Diversity Using Petasis Reactions and 1,3-Dipolar Cycloadditions

A short and modular synthetic pathway using intramolecular 1,3-dipolar cycloaddition reactions and yielding functionalized isoxazoles, isoxazolines, and isoxazolidines is described. The change in shape of previous compounds and those in this study is quantified and compared using principal moment-of-inertia shape analysis.Chemistry and Chemical Biolog

The Schnitzler syndrome

The Schnitzler syndrome is a rare and underdiagnosed entity which is considered today as being a paradigm of an acquired/late onset auto-inflammatory disease. It associates a chronic urticarial skin rash, corresponding from the clinico-pathological viewpoint to a neutrophilic urticarial dermatosis, a monoclonal IgM component and at least 2 of the following signs: fever, joint and/or bone pain, enlarged lymph nodes, spleen and/or liver, increased ESR, increased neutrophil count, abnormal bone imaging findings. It is a chronic disease with only one known case of spontaneous remission. Except of the severe alteration of quality of life related mainly to the rash, fever and pain, complications include severe inflammatory anemia and AA amyloidosis. About 20% of patients will develop a lymphoproliferative disorder, mainly Waldenström disease and lymphoma, a percentage close to other patients with IgM MGUS. It was exceedingly difficult to treat patients with this syndrome until the IL-1 receptor antagonist anakinra became available. Anakinra allows a complete control of all signs within hours after the first injection, but patients need continuous treatment with daily injections

Skeletal Diversification via Heteroatom Linkage Control: Preparation of Bicyclic and Spirocyclic Scaffolds from NSubstituted Homopropargyl Alcohols

The discovery and application of a new branching pathway synthesis strategy that rapidly produces skeletally diverse scaffolds is described. Two different scaffold types, one a bicyclic iodo-vinylidene tertiary amine/tertiary alcohol and the other, a spirocyclic 3-furanone, are each obtained using a two-step sequence featuring a common first step. Both scaffold types lead to intermediates that can be orthogonally diversified using the same final components. One of the scaffold types was obtained in sufficiently high yield that it was immediately used to produce a 97-compound library