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Objective: Exosomes (Exos) are membrane-encased vesicles derived by nearly all cell types for intercellular communication and regulation. They also received attention for their use as natural therapeutic platforms and drug delivery system. Classically activated M1 macrophages suppress tumor growth by releasing pro-inflammatory factors. This study investigated the suitability of M1-exosomes (M1-Exos) as drug carrier and their effect on the NF-κB signal pathway and further detected whether macrophages repolarization can potentiate the antitumor activities of chemotherapeutics. Methods: M1-Exos were isolated from M1-macrophages by ultracentrifugation and characterized by transmission electron, nanoparticle tracking analysis, dynamic light scattering and western blot. Then M1-Exos were used as Paclitaxel (PTX) carriers to prepare a nano-formulation (PTX- M1-Exos). A relatively simple slight sonication method was used to prepare the drug delivery system (PTX-M1-Exos). The cytotoxicity of PTX-M1-Exos on cancer cells was detected by MTT and flow cytometry in vitr o. 4T1 tumor bearing mice were used to perform the therapeutic effect of PTX-M1-Exos in vivo . Results: The expression of caspase-3 in breast cancer cells was increased when co-incubated with macrophages in the presence of M1-Exos in vitro . The production of pro-inflammatory cytokines was increased after exposure of macrophages in M1-Exos. M1-Exos provided a pro-inflammatory environment which enhanced the anti-tumor activity via caspase-3 mediated pathway. The treatment of M1-Exos to the tumor bearing mice exhibit anti-tumor effects in vivo . Meanwhile, the treatment of PTX-M1-Exos demonstrated higher anti-tumor effects than the M1-Exos or PTX group. Conclusion: The results in our study indicate that the M1-Exos act as the carrier to deliver PTX into the tumor tissues, and also enhance the anti-tumor effects of chemotherapeutics in tumor bearing mice.

Cayman ataxia is a recessive congenital ataxia restricted to one area of Grand Cayman Island. Comparative mapping suggested that the locus on 19p13.3 associated with Cayman ataxia might be homologous to the locus on mouse chromosome 10 associated with the recessive ataxic mouse mutant jittery. Screening genes in the region of overlap identified mutations in a novel predicted gene in three mouse jittery alleles, including the first mouse mutation caused by an Alu-related (B1 element) insertion. We found two mutations exclusively in all individuals with Cayman ataxia. The gene ATCAY or Atcay encodes a neuron-restricted protein called caytaxin. Caytaxin contains a CRAL-TRIO motif common to proteins that bind small lipophilic molecules. Mutations in another protein containing a CRAL-TRIO domain, alpha-tocopherol transfer protein (TTPA), cause a vitamin E-responsive ataxia. Three-dimensional protein structural modeling predicts that the caytaxin ligand is more polar than vitamin E. Identification of the caytaxin ligand may help develop a therapy for Cayman ataxia.

Phenotypes that might otherwise reveal a gene’s function can be obscured by genes with overlapping function. This phenomenon is best-known within gene families, where an important shared function may only be revealed by mutating all family members. Here we describe the ‘Green Monster’ technology enabling the precise deletion of many genes. In this method, a population of deletion strains with each deletion marked by an inducible green fluorescent protein (GFP) reporter gene, is subjected to repeated rounds of mating, meiosis, and flow-cytometric enrichment. This results in the aggregation of multiple deletion loci within single cells. The Green Monster strategy is potentially applicable to assembling other engineered alterations in any species with sex or alternative means of allelic assortment. To demonstrate the technology, we generated a single broadly drug-sensitive strain of Saccharomyces cerevisiae bearing precise deletions of all 16 adenosine triphosphate-binding cassette transporters within clades associated with multi-drug resistance.

The devastating plant pathogen Sclerotinia sclerotiorum produces copious (up to 50 mM) amounts of oxalic acid, which, for over a quarter century, has been claimed as the pathogenicity determinant based on UV-induced mutants that concomitantly lost oxalate production and pathogenicity. Such a claim was made without fulfilling the molecular Koch's postulates because the UV mutants are genetically undefined and harbour a developmental defect in sclerotial production. Here, we generated oxalate-minus mutants of S. sclerotiorum using two independent mutagenesis techniques, and tested the resulting mutants for growth at different pHs and for pathogenicity on four host plants. The oxalate-minus mutants accumulated fumaric acid, produced functional sclerotia and have reduced ability to acidify the environment. The oxalate-minus mutants retained pathogenicity on plants, but their virulence varied depending on the pH and buffering capacity of host tissue. Acidifying the host tissue enhanced virulence of the oxalate-minus mutants, whereas supplementing with oxalate did not. These results suggest that it is low pH, not oxalic acid itself, that establishes the optimum conditions for growth, reproduction, pathogenicity and virulence expression of S. sclerotiorum. Exonerating oxalic acid as the primary pathogenicity determinant will stimulate research into identifying additional candidates as pathogenicity factors towards better understanding and managing Sclerotinia diseases.

Satisfactory and unsatisfactory hips show different patterns of acetabular development after reduction. AI, CEA and RI are all predictors of final radiographic outcomes in DDH treated by CR, although AI showed the best results. AI continues to improve until seven years after CR in hips with satisfactory outcomes, while it ceases to improve three to four years after CR in hips with unsatisfactory outcomes. According to our results, surgery is indicated if AI >28° 1 year following CR or AI >25° two to four years after CR. CEA and RI should be used as a secondary index to aid in the selection of patients requiring surgery.

Stemphylium blight (caused by Stemphylium botryosum Wallr.) is one of the major diseases of lentil (Lens culinaris Medik.) in South Asia and North America. The objective of the study was to identify linkage map position of the genes conferring resistance to stemphylium blight and the markers linked to the genes for its utilization in marker‐assisted breeding. A population of 206 F7–derived recombinant inbred lines (RILs) was developed from a cross between ILL‐6002 (resistant) and ILL‐5888 (susceptible). The RILs were planted in disease‐screening plots at Ishurdi, Bangladesh in the 2006–2007 and 2008–2009 winter cropping seasons. Significant variation was detected among RILs for disease scores and frequency distributions suggested complex inheritance. An intraspecific linkage map was constructed that comprised 139 markers; 21 simple sequence repeats (SSR), 27 randomly amplified polymorphic DNA (RAPD), 89 sequence related amplified polymorphism (SRAP) markers and 2 morphological markers distributed over 14 linkage groups. One significant quantitative trait loci (QTL) was detected based on disease scores from the 2006–2007 experiment while three significant QTLs were detected from the 2008–2009 experiment. The QTL QLG480–81 was common in both years and accounted for 25.2 and 46.0% of the variation of disease scores in 2006–2007 and 2008–2009 experiments, respectively. Two SRAP markers, ME5XR10 and ME4XR16c, and one RAPD marker, UBC34, located on linkage group 4, were significantly associated with the QLG480–81 in both crop years. After validation, the more tightly linked ME4XR16c marker may be used for marker assisted selection for stemphylium blight resistance.

The objective of this study was to investigate the expression, proliferation, and apoptosis function of long-chain non-coding RNA maternally expressed gene 3 (MEG3) and antisense non-coding RNA at the INK4 locus (ANRIL) in gallbladder cancer (GBC) tissues. GBC tissues and adjacent normal samples were collected from 84 patients from January 2008 to June 2010. Empty vector, pcDNA-MEG3, and pcDNA-ANRIL vectors were transfected into GBC-SD and QBC939 cells. An MTT assay, real-time quantitative polymerase chain reaction (RT-qPCR), flow cytometry, Western blotting, and immunohistochemistry were applied. The effects of MEG3 and ANRIL were also verified in mice. Compared with normal tissues, the expression of MEG3 was significantly lower in GBC tissues, whereas the expression of ANRIL was significantly higher (both P < 0.05). The overexpression of MEG3 and underexpression of ANRIL were significantly associated with GBC prognosis (both P < 0.05). The expressions of MEG3 and ANRIL were higher in pcDNA-MEG3 and pcDNA-ANRIL-transfected cells than in empty vector-transfected cells in vitro (both P < 0.05). Most of the pcDNA-MEG3-transfected cells were in the G0-G1 phase, which showed reduced cell activity and clone counts and increased p53 and decreased cyclin D1, whereas the pcDNA-ANRIL-transfected cells were mostly in the S phase and showed contrasting behavior. Mice injected with pcDNA-MEG3-transfected cells had smaller and lighter tumors, decreased ki-67 levels, and increased caspase 3 levels, whereas those injected with pcDNA-ANRIL showed contrasting results (all P < 0.05). MEG3 can inhibit the proliferation of GBC cells and promote apoptosis, whereas ANRIL can improve the proliferation of gallbladder cells and inhibit apoptosis. Collectively, our results suggest that therapeutic strategies directed toward upregulating MEG3 and downregulating ANRIL may be clinically relevant for the inhibition of GBC deterioration.