32 research outputs found

    Invasive mosquito species in Europe and Serbia, 1979 – 2011

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    People’s increased mobility and international trade play important roles in the dissemination of vectors and the pathogens that they could transmit. Climate change is likely to become another important consideration in the near future. The responses of insects to these changes (in addition to potential for increased vector capacity) could allow for a broadening of their colonized areas and the invasion of new sites. In the last couple of years a number of pathogen introductions into Europe have been recorded. The latest (Ravenna, Italy, 2007) was caused by the tropical Chikungunya virus, which is transmitted by the “Asian tiger mosquito”, a species introduced into Europe in 1979 (Albania), and then Italy in 1990. Invasion continued to France in 1999 and until present, Belgium, Montenegro, Greece, Switzerland, Croatia, Spain, Bosnia and Herzegovina, the Netherlands, Slovenia, Germany, Serbia, Bulgaria and Turkey have been invaded. Deciphering the true cause of changes in the distribution of mosquitoes is difficult and complex and depends, to a great extent, on the availability of data obtained by monitoring. In order to assist in vector-borne disease preparedness, distribution of the most important invasive species St. albopicta in Europe and particulars of findings in Serbia are conferred

    Feasibility, acceptability, and effectiveness of non-pharmaceutical interventions against infectious diseases among crisis-affected populations: a scoping review

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    BACKGROUND: Colonization of large part of Europe by the Asian tiger mosquito Aedes albopictus is causing autochthonous transmission of chikungunya and dengue exotic arboviruses. While pyrethroids are recommended only to reduce/limit transmission, they are widely implemented to reduce biting nuisance and to control agricultural pests, increasing the risk of insurgence of resistance mechanisms. Worryingly, pyrethroid resistance (with mortality < 70%) was recently reported in Ae. albopictus populations from Italy and Spain and associated with the V1016G point mutation in the voltage-sensitive sodium channel gene conferring knockdown resistance (kdr). Genotyping pyrethroid resistance-associated kdr mutations in field mosquito samples represents a powerful approach to detect early signs of resistance without the need for carrying out phenotypic bioassays which require availability of live mosquitoes, dedicated facilities and appropriate expertise. METHODS: Here we report results on the PCR-genotyping of the V1016G mutation in 2530 Ae. albopictus specimens from 69 sampling sites in 19 European countries. RESULTS: The mutation was identified in 12 sites from nine countries (with allele frequencies ranging from 1 to 8%), mostly distributed in two geographical clusters. The western cluster includes Mediterranean coastal sites from Italy, France and Malta as well as single sites from both Spain and Switzerland. The eastern cluster includes sites on both sides of the Black Sea in Bulgaria, Turkey and Georgia as well as one site from Romania. These results are consistent with genomic data showing high connectivity and close genetic relationship among West European populations and a major barrier to gene flow between West European and Balkan populations. CONCLUSIONS: The results of this first effort to map kdr mutations in Ae. albopictus on a continental scale show a widespread presence of the V1016G allele in Europe, although at lower frequencies than those previously reported from Italy. This represents a wake-up call for mosquito surveillance programs in Europe to include PCR-genotyping of pyrethroid resistance alleles, as well as phenotypic resistance assessments, in their routine activities

    Geographic distribution of the V1016G knockdown resistance mutation in aedes albopictus. A warning bell for Europe

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    Background: Colonization of large part of Europe by the Asian tiger mosquito Aedes albopictus is causing autochthonous transmission of chikungunya and dengue exotic arboviruses. While pyrethroids are recommended only to reduce/limit transmission, they are widely implemented to reduce biting nuisance and to control agricultural pests, increasing the risk of insurgence of resistance mechanisms. Worryingly, pyrethroid resistance (with mortality &lt; 70%) was recently reported in Ae. albopictus populations from Italy and Spain and associated with the V1016G point mutation in the voltage-sensitive sodium channel gene conferring knockdown resistance (kdr). Genotyping pyrethroid resistance-associated kdr mutations in field mosquito samples represents a powerful approach to detect early signs of resistance without the need for carrying out phenotypic bioassays which require availability of live mosquitoes, dedicated facilities and appropriate expertise.Methods: Here we report results on the PCR-genotyping of the V1016G mutation in 2530 Ae. albopictus specimens from 69 sampling sites in 19 European countries.Results: The mutation was identified in 12 sites from nine countries (with allele frequencies ranging from 1 to 8%), mostly distributed in two geographical clusters. The western cluster includes Mediterranean coastal sites from Italy, France and Malta as well as single sites from both Spain and Switzerland. The eastern cluster includes sites on both sides of the Black Sea in Bulgaria, Turkey and Georgia as well as one site from Romania. These results are consistent with genomic data showing high connectivity and close genetic relationship among West European populations and a major barrier to gene flow between West European and Balkan populations.Conclusions: The results of this first effort to map kdr mutations in Ae. albopictus on a continental scale show a widespread presence of the V1016G allele in Europe, although at lower frequencies than those previously reported from Italy. This represents a wake-up call for mosquito surveillance programs in Europe to include PCR-genotyping of pyrethroid resistance alleles, as well as phenotypic resistance assessments, in their routine activities

    Telomerase inhibition abolishes the tumorigenicity of pediatric ependymoma tumor-initiating cells

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    Pediatric ependymomas are highly recurrent tumors resistant to conventional chemotherapy. Telomerase, a ribonucleoprotein critical in permitting limitless replication, has been found to be critically important for the maintenance of tumor-initiating cells (TICs). These TICs are chemoresistant, repopulate the tumor from which they are identified, and are drivers of recurrence in numerous cancers. In this study, telomerase enzymatic activity was directly measured and inhibited to assess the therapeutic potential of targeting telomerase. Telomerase repeat amplification protocol (TRAP) (n = 36) and C-circle assay/telomere FISH/ATRX staining (n = 76) were performed on primary ependymomas to determine the prevalence and prognostic potential of telomerase activity or alternative lengthening of telomeres (ALT) as telomere maintenance mechanisms, respectively. Imetelstat, a phase 2 telomerase inhibitor, was used to elucidate the effect of telomerase inhibition on proliferation and tumorigenicity in established cell lines (BXD-1425EPN, R254), a primary TIC line (E520) and xenograft models of pediatric ependymoma. Over 60 % of pediatric ependymomas were found to rely on telomerase activity to maintain telomeres, while no ependymomas showed evidence of ALT. Children with telomerase-active tumors had reduced 5-year progression-free survival (29 +/- A 11 vs 64 +/- A 18 %; p = 0.03) and overall survival (58 +/- A 12 vs 83 +/- A 15 %; p = 0.05) rates compared to those with tumors lacking telomerase activity. Imetelstat inhibited proliferation and self-renewal by shortening telomeres and inducing senescence in vitro. In vivo, Imetelstat significantly reduced subcutaneous xenograft growth by 40 % (p = 0.03) and completely abolished the tumorigenicity of pediatric ependymoma TICs in an orthotopic xenograft model. Telomerase inhibition represents a promising therapeutic approach for telomerase-active pediatric ependymomas found to characterize high-risk ependymomas.Canadian Institutes of Health Research [MOP 82727]info:eu-repo/semantics/publishedVersio

    Cdh11 Acts as a Tumor Suppressor in a Murine Retinoblastoma Model by Facilitating Tumor Cell Death

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    CDH11 gene copy number and expression are frequently lost in human retinoblastomas and in retinoblastomas arising in TAg-RB mice. To determine the effect of Cdh11 loss in tumorigenesis, we crossed Cdh11 null mice with TAg-RB mice. Loss of Cdh11 had no gross morphological effect on the developing retina of Cdh11 knockout mice, but led to larger retinal volumes in mice crossed with TAg-RB mice (p = 0.01). Mice null for Cdh11 presented with fewer TAg-positive cells at postnatal day 8 (PND8) (p = 0.01) and had fewer multifocal tumors at PND28 (p = 0.016), compared to mice with normal Cdh11 alleles. However, tumor growth was faster in Cdh11-null mice between PND8 and PND84 (p = 0.003). In tumors of Cdh11-null mice, cell death was decreased 5- to 10-fold (p<0.03 for all markers), while proliferation in vivo remained unaffected (p = 0.121). Activated caspase-3 was significantly decreased and β-catenin expression increased in Cdh11 knockdown experiments in vitro. These data suggest that Cdh11 displays tumor suppressor properties in vivo and in vitro in murine retinoblastoma through promotion of cell death

    Superconducting spintronics

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    The interaction between superconducting and spin-polarized orders has recently emerged as a major research field following a series of fundamental breakthroughs in charge transport in superconductor-ferromagnet heterodevices which promise new device functionality. Traditional studies which combine spintronics and superconductivity have mainly focused on the injection of spin-polarized quasiparticles into superconducting materials. However, a complete synergy between superconducting and magnetic orders turns out to be possible through the creation of spin-triplet Cooper pairs which are generated at carefully engineered superconductor interfaces with ferromagnetic materials. Currently, there is intense activity focused on identifying materials combinations which merge superconductivity and spintronics in order to enhance device functionality and performance. The results look promising: it has been shown, for example, that superconducting order can greatly enhance central effects in spintronics such as spin injection and magnetoresistance. Here, we review the experimental and theoretical advances in this field and provide an outlook for upcoming challenges related to the new concept of superconducting spintronics.J.L. was supported by the Research Council of Norway, Grants No. 205591 and 216700. J.W.A.R. was supported by the UK Royal Society and the Leverhulme Trust through an International Network Grant (IN-2013-033).This is the accepted manuscript. The final version is available at http://www.nature.com/nphys/journal/v11/n4/full/nphys3242.html

    No ocean acidification effects on shell growth and repair in the New Zealand brachiopod Calloria inconspicua (Sowerby, 1846)

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    AbstractSurface seawaters are becoming more acidic due to the absorption of rising anthropogenic CO2. Marine calcifiers are considered to be the most vulnerable organisms to ocean acidification due to the reduction in the availability of carbonate ions for shell or skeletal production. Rhychonelliform brachiopods are potentially one of the most calcium carbonate-dependent groups of marine organisms because of their large skeletal content. Little is known, however, about the effects of lowered pH on these taxa. A CO2 perturbation experiment was performed on the New Zealand terebratulide brachiopod Calloria inconspicua to investigate the effects of pH conditions predicted for 2050 and 2100 on the growth rate and ability to repair shell. Three treatments were used: an ambient pH control (pH 8.16), a mid-century scenario (pH 7.79), and an end-century scenario (pH 7.62). The ability to repair shell was not affected by acidified conditions with &amp;gt;80% of all damaged individuals at the start of the experiment completing shell repair after 12 weeks. Growth rates in undamaged individuals &amp;gt;3 mm in length were also not affected by lowered pH conditions, whereas undamaged individuals &amp;lt;3 mm grew faster at pH 7.62 than the control. The capability of C. inconspicua to continue shell production and repair under acidified conditions suggests that this species has a robust control over the calcification process, where suitable conditions at the site of calcification can be generated across a range of pH conditions.The authors would like to thank the science support staff at the Portobello Marine Laboratory, University of Otago, for their help in the set up and maintenance of the ocean acidification experimental system. Thanks also to Kim Currie at National Institute of Water and Atmospheric Research for the DIC and total alkalinity measurements. ELC is supported by the NERC PhD Studentship (NE/T/A/ 2011).This is the final version of the article. It first appeared from Oxford University Press via http://dx.doi.org/10.1093/icesjms/fsv03

    Blood groups and acute aortic dissection type III

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    Copyright © 2016 Termedia & Banach. Introduction: Acute aortic type III dissection is one of the most catastrophic events, with in-hospital mortality ranging between 10% and 12%. The majority of patients are treated medically, but complicated dissections, which represent 15% to 20% of cases, require surgical or thoracic endovascular aortic repair (TEVAR). For the best outcomes adequate blood transfusion support is required. Interest in the relationship between blood type and vascular disease has been established. The aim of our study is to evaluate distribution of blood groups among patients with acute aortic type III dissection and to identify any kind of relationship between blood type and patient's survival. Material and methods: From January 2005 to December 2014, 115 patients with acute aortic type III dissection were enrolled at the Clinic of Vascular and Endovascular Surgery in Belgrade, Serbia and retrospectively analyzed. Patients were separated into two groups. The examination group consisted of patients with a lethal outcome, and the control group consisted of patients who survived. Results: The analysis of the blood groups and RhD typing between groups did not reveal a statistically significant difference (p = 0.220). Conclusions: Our results indicated no difference between different blood groups and RhD typing with respect to in-hospital mortality of patients with acute aortic dissection type III
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