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31.
Dongjing Zhang Rosemary Susan Lees Zhiyong Xi Jeremie R. L. Gilles Kostas Bourtzis 《PloS one》2015,10(8)
Due to the absence of a perfect method for mosquito sex separation, the combination of the sterile insect technique and the incompatible insect technique is now being considered as a potentially effective method to control Aedes albopictus. In this present study first we examine the minimum pupal irradiation dose required to induce complete sterility in Wolbachia triple-infected (HC), double-infected (GUA) and uninfected (GT) female Ae. albopictus. The HC line is a candidate for Ae. albopictus population suppression programmes, but due to the risk of population replacement which characterizes this triple infected line, the individuals to be released need to be additionally irradiated. After determining the minimum irradiation dose required for complete female sterility, we test whether sterilization is sufficient to prevent invasion of the triple infection from the HC females into double-infected (GUA) populations. Our results indicate that irradiated Ae. albopictus HC, GUA and GT strain females have decreased fecundity and egg hatch rate when irradiated, inversely proportional to the dose, and the complete sterilization of females can be acquired by pupal irradiation with doses above 28 Gy. PCR-based analysis of F1 and F2 progeny indicate that the irradiated HC females, cannot spread the new Wolbachia wPip strain into a small cage GUA population, released at a 1:5 ratio. Considering the above results, we conclude that irradiation can be used to reduce the risk of population replacement caused by an unintentional release of Wolbachia triple-infected Ae. albopictus HC strain females during male release for population suppression. 相似文献
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33.
Sofia Agelaki Antonia Kalykaki Harris Markomanolaki Maria A. Papadaki Galatea Kallergi Dora Hatzidaki Kostas Kalbakis Dimitrios Mavroudis Vassilis Georgoulias 《PloS one》2015,10(6)
Background
To evaluate the efficacy of lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, in therapy-resistant HER2-positive CTCs in metastatic breast cancer (MBC).Patients and Methods
Patients with MBC and HER2-positive CTCs despite disease stabilization or response to prior therapy, received lapatinib 1500 mg daily in monthly cycles, till disease progression or CTC increase. CTC monitoring was performed by immunofluorescent microscopy using cytospins of peripheral blood mononuclear cells (PBMCs) double stained for HER2 or EGFR and cytokeratin.Results
A total of 120 cycles were administered in 22 patients; median age was 62.5 years, 15 (68.2%) patients were post-menopausal and 20 (90.1%) had HER2-negative primary tumors. At the end of the second course, HER2-positive CTC counts decreased in 76.2% of patients; the median number of HER2-positive CTCs/patient also declined significantly (p = 0.013), however the decrease was significant only among patients presenting disease stabilization (p = 0.018) but not among those with disease progression during lapatinib treatment. No objective responses were observed. All CTC-positive patients harbored EGFR-positive CTCs on progression compared to 62.5% at baseline (p = 0.054). The ratio of EGFR-positive CTCs/total CTCs detected in all patients increased from 17.1% at baseline to 37.6% on progression, whereas the mean percentage of HER2-negative CTCs/patient increased from 2.4% to 30.6% (p = 0.03).Conclusions
The above results indicate that lapatinib is effective in decreasing HER2-positive CTCs in patients with MBC irrespectively of the HER2 status of the primary tumor and imply the feasibility of monitoring the molecular changes on CTCs during treatment with targeted agents.Trial Registration
Clinical trial.gov NCT00694252 相似文献34.
Klaus Schümann Nadia Herbach Christina Kerling Markus Seifert Carine Fillebeen Isabella Prysch Jens Reich Günter Weiss Kostas Pantopoulos 《Journal of trace elements in medicine and biology》2010,24(1):58-66
Hemizygous TNFΔARE/+ mice are a murine model for chronic inflammation. We utilized these animals to study iron-kinetics and corresponding protein expression in an iron-deficient and iron-adequate setting. 59Fe-absorption was determined in ligated duodenal loops in vivo. Whole body distribution of i.v. injected 59Fe was analysed, and the organ specific expression of ferroportin, transferrin receptor-1, hepcidin and duodenal DMT-1 was quantified by real-time PCR and Western blotting.Duodenal 59Fe-lumen-to-body transport was not affected by the genotype. Duodenal 59Fe-retention was increased in TNFΔARE/+ mice, suggesting higher 59Fe-losses with defoliated enterocytes. Iron-deficiency increased duodenal 59Fe-lumen-to-body transport, and higher duodenal 59Fe-tissue retention went along with higher duodenal DMT-1, ferroportin, and liver hepcidin expression. TNFΔARE/+ mice significantly increase their 59Fe-content in inflamed joints and ilea, and correspondingly reduce splenic 59Fe-content. Leukocyte infiltrations in the joints suggest a substantial shift of iron-loaded RES cells to inflamed tissues as the underlying mechanism. This finding was paralleled by increased non-haem iron content in joints and reduced haemoglobin and haematocrit concentrations in TNFΔARE/+ mice.In conclusion, erythropoiesis in inflamed TNFΔARE/+ mice could be iron-limited due to losses with exfoliated iron-loaded enterocytes and/or to increased iron-retention in RES cells that shift from the spleen to inflamed tissues. 相似文献
35.
The authors present an annotated list of rare or otherwise interesting vascular plants collected in the mountains of northern Greece by themselves in 1979 and by Strid and Georgiadou in 1977. The following are apparently new to Greece: Thesium linophyllon L. ssp. montanum (Ehrh. ex. Hoffm.) Čelak., Moehringia pendulo (Waldst. & Kit.) Fenzl, Gypsophila glomerata Pallas ex. Bieb., Dianthus peiraeus Waldst. & Kit. ssp. noeanus (Boiss.) Tutin, Dianthus superbus L., Ranunculus fon–tanus C. Presl, Thlaspi arvense L., Potentilla apennina Ten. ssp. stoianovii Urum. & Jav., Trifolium badium Schreber, Rhamnus pumila Turra, Viola palustris L., Athamanta albanica Alston & Sandwith, Peucedanum oligophyllum ssp. aequiradium (Vandas) Tutin, Vaccinium gaultherioides Bigelow, Galeopsis speciosa Miller, G. bifida Boenn., Melampyrum sylvaticum L., Odontites lutea (L.) Clairv., Sambucus racemosa L., Symphyandra wanneri (Rochel) Heuffel, Galinsoga parviflora Cav., Achillea distans Waldst. & Kit. ex Willd., Centaurea grbavacensis (Rohlena) Stoj. & Acht., C. indurata Janka, Lactuca aurea (Schultz Bip. ex PanČić) Stebbins, Festuca gigantea (L.) Vill., F. pirinica Horvat ex Markgr.–Dannenb., Sparganium minimum (Hartm.) Fries, and Rhynchospora alba (L.) Vahl. 相似文献
36.
37.
Repanas K Zingler N Layer LE Schumann GG Perrakis A Weichenrieder O 《Nucleic acids research》2007,35(14):4914-4926
The human LINE-1 endonuclease (L1-EN) is the targeting endonuclease encoded by the human LINE-1 (L1) retrotransposon. L1-EN guides the genomic integration of new L1 and Alu elements that presently account for ~28% of the human genome. L1-EN bears considerable technological interest, because its target selectivity may ultimately be engineered to allow the site-specific integration of DNA into defined genomic locations. Based on the crystal structure, we generated L1-EN mutants to analyze and manipulate DNA target site recognition. Crystal structures and their dynamic and functional analysis show entire loop grafts to be feasible, resulting in altered specificity, while individual point mutations do not change the nicking pattern of L1-EN. Structural parameters of the DNA target seem more important for recognition than the nucleotide sequence, and nicking profiles on DNA oligonucleotides in vitro are less well defined than the respective integration site consensus in vivo. This suggests that additional factors other than the DNA nicking specificity of L1-EN contribute to the targeted integration of non-LTR retrotransposons. 相似文献
38.
Douroumis D Fatouros DG Bouropoulos N Papagelis K Tasis D 《International journal of nanomedicine》2007,2(4):761-766
Within the family of nanomaterials, carbon nanotubes (CNTs) have emerged as a new efficient scaffold for studying molecular interactions at interfaces. Poor dispersability of CNTs in any solvent presents a considerable drawback for the development of novel functional composite structures. Previous studies have demonstrated that the solubility of CNTs can be greatly enhanced by employing appropriate surfactants, some of them being biological molecules. In this work, we study the noncovalent wrapping of lipid chains onto the graphitic surface of single-walled material (SWCNTs) by electron microscopy and Raman spectroscopy. Stable and homogenous aqueous suspensions of SWCNTs in the presence of lipids have been prepared, whereas their electrophoretic mobility was confirmed by zeta-potential measurements. Raman measurements revealed that smaller diameter SWCNTs are preferentially dispersed by lipid molecules in the aqueous supernatant part of the prepared suspension. 相似文献
39.
The small Tims are chaperones that facilitate insertion of hydrophobic precursors into the inner mitochondrial membrane. We purified Tim12 and found it forms dimers that bind to Tim9. In this interaction, Tim12 undergoes structural changes that may be important for transport of its substrates in the mitochondrial carrier import pathway. 相似文献
40.
De Savi C Morley AD Ting A Nash I Karabelas K Wood CM James M Norris SJ Karoutchi G Rankine N Hamlin G Macfaul PA Ryan D Baker SV Hargreaves D Gerhardt S 《Bioorganic & medicinal chemistry letters》2011,21(14):4215-4219
Directed screening has identified a novel series of MMP13 inhibitors that possess good levels of activity whilst possessing excellent selectivity over related MMPs. The binding mode of the series has been solved by co-crystallisation and demonstrates an interesting mode of inhibition without interaction with the catalytic zinc atom. 相似文献