55 research outputs found

    The Cytoskeleton in Papillomavirus Infection

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    Cytoskeleton defines the shape and structural organization of the cell. Its elements participate in cell motility, intracellular transport and chromosome movement during mitosis. Papillomaviruses (PV) are strictly epitheliotropic and induce self-limiting benign tumors of skin and mucosa, which may progress to malignancy. Like many other viruses, PV use the host cytoskeletal components for several steps during their life cycle. Prior to internalization, PV particles are transported along filopodia to the cell body. Following internalization, retrograde transport along microtubules via the dynein motor protein complex is observed. In addition, viral minichromosomes depend on the host cell machinery for partitioning of viral genomes during mitosis, which may be affected by oncoproteins E6 and E7 of high-risk human PV types. This mini-review summarizes recent advances in our understanding of papillomavirus’ interactions with the host cell cytoskeletal elements

    Complex population structure and haplotype patterns in the Western European honey bee from sequencing a large panel of haploid drones:Sequencing haploid honey bee drones

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    International audienceHoney bee subspecies originate from specific geographical areas in Africa, Europe and the Middle East, and beekeepers interested in specific phenotypes have imported genetic material to regions outside of the bees' original range for use either in pure lines or controlled crosses. Moreover, imported drones are present in the environment and mate naturally with queens from the local subspecies. The resulting admixture complicates population genetics analyses, and population stratification can be a major problem for association studies. To better understand Western European honey bee populations, we produced a whole genome sequence and single nucleotide polymorphism (SNP) genotype data set from 870 haploid drones and demonstrate its utility for the identification of nine genetic backgrounds and various degrees of admixture in a subset of 629 samples. Five backgrounds identified correspond to subspecies, two to isolated populations on islands and two to managed populations. We also highlight several large haplotype blocks, some of which coincide with the position of centromeres. The largest is 3.6 Mb long and represents 21% of chromosome 11, with two major haplotypes corresponding to the two dominant genetic backgrounds identified. This large naturally phased data set is available as a single vcf file that can now serve as a reference for subsequent populations genomics studies in the honey bee, such as (i) selecting individuals of verified homogeneous genetic backgrounds as references, (ii) imputing genotypes from a lower-density data set generated by an SNP-chip or by low-pass sequencing, or (iii) selecting SNPs compatible with the requirements of genotyping chips

    Evaluation of Suppressed Mite Reproduction (SMR) Reveals Potential for Varroa Resistance in European Honey Bees (Apis melliferaL.)

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    Simple Summary The miteVarroa destructorrepresents a great threat to honey bees and the beekeeping industry. The opportunity to select and breed honey bees that are naturally able to fight the mite stands a sustainable solution. This can be achieved by evaluation of the failure of mite reproduction (SMR, suppressed mite reproduction). We conducted a large European experiment to assess the SMR trait in different populations of honey bees spread over 13 different countries, and representing different honey bee populations. The first goal was to standardize and validate the SMR evaluation method, and then to compare the SMR trait between the different populations. Our results indicate that it is necessary to examine at least 35 brood cells infested by a single mite to reliably estimate the SMR score of any given colony. Several colonies from our dataset display high SMR scores, indicating that this trait is present within the European honey bee populations. No major differences could be identified between countries for a given population, or between populations in different countries. This study shows the potential to increase selection efforts to breedV. destructorhoney bee resistant populations. In the fight against theVarroa destructormite, selective breeding of honey bee (Apis melliferaL.) populations that are resistant to the parasitic mite stands as a sustainable solution. Selection initiatives indicate that using the suppressed mite reproduction (SMR) trait as a selection criterion is a suitable tool to breed such resistant bee populations. We conducted a large European experiment to evaluate the SMR trait in different populations of honey bees spread over 13 different countries, and representing different honey bee genotypes with their local mite parasites. The first goal was to standardize and validate the SMR evaluation method, and then to compare the SMR trait between the different populations. Simulation results indicate that it is necessary to examine at least 35 single-infested cells to reliably estimate the SMR score of any given colony. Several colonies from our dataset display high SMR scores indicating that this trait is present within the European honey bee populations. The trait is highly variable between colonies and some countries, but no major differences could be identified between countries for a given genotype, or between genotypes in different countries. This study shows the potential to increase selective breeding efforts ofV. destructorresistant populations

    Queen rearing and selection practices and their impact on the genetic diversity and fitness of honey bee colonies

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    The Apimondia working group on honey bee diversity and fitness (AWG 7) was created on October 25, 2010 as a Scientific Working Group of Apimondia. The aim of this AWG is to collect information on honey bee queen rearing practices, and examine their impact on the genetic variability and general health of honey bee colonies. The AWG consists of 23 members from 16 different countries. The world wide survey being conducted by this AWG is focused on gathering information on how selection methods, instrumental insemination, disease management procedures, introduction of exotic bee lines, queen replacement strategies, and loss of local colony populations due to introduced parasites and pathogens, affect the ability of our bees to survive and reproduce. The information collected will contribute on an international level to our understanding of how apiculture practices affect honey bee genetics, health and productivity

    Target Cell Cyclophilins Facilitate Human Papillomavirus Type 16 Infection

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    Following attachment to primary receptor heparan sulfate proteoglycans (HSPG), human papillomavirus type 16 (HPV16) particles undergo conformational changes affecting the major and minor capsid proteins, L1 and L2, respectively. This results in exposure of the L2 N-terminus, transfer to uptake receptors, and infectious internalization. Here, we report that target cell cyclophilins, peptidyl-prolyl cis/trans isomerases, are required for efficient HPV16 infection. Cell surface cyclophilin B (CyPB) facilitates conformational changes in capsid proteins, resulting in exposure of the L2 N-terminus. Inhibition of CyPB blocked HPV16 infection by inducing noninfectious internalization. Mutation of a putative CyP binding site present in HPV16 L2 yielded exposed L2 N-terminus in the absence of active CyP and bypassed the need for cell surface CyPB. However, this mutant was still sensitive to CyP inhibition and required CyP for completion of infection, probably after internalization. Taken together, these data suggest that CyP is required during two distinct steps of HPV16 infection. Identification of cell surface CyPB will facilitate the study of the complex events preceding internalization and adds a putative drug target for prevention of HPV–induced diseases

    GENDER AND MULTICULTURALISM (Gender i wielokulturowosc)

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    The aim of the article is a reflection on the narrow understanding of multiculturalism in Poland. The author shows the possibilities offered by the combination of different theoretical perspectives, including critical research on social minorities. In the Polish discussion of multiculturalism gender issues constitute a new topic, which used to be ignored in the general discourse on the relations between minorities and the dominant group

    What we know and what we don’t know about early-developmental support and education of DHH children in five European countries

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    This proposition will present five European national systems of support for deaf and hard-of-hearing (DHH) children and their families. The countries are: Poland, Slovakia, Germany, France, Switzerland. The purpose is to compare different systemic and institutional solutions existing as a result of political, social and educational decisions, defined as support (diagnosis, hearing aids, rehabilitation, educational systems) for DHH. Two of chosen countries Poland and Slovakia have joined the structures of the EU later. Consequently the initiatives aimed at creating equal opportunities for disabled people have been based on other initial matters. The experience of French, German teachers has left its imprint on the solutions applied in other countries. An interesting issue is how it is solved in multilingual and multicultural Switzerland. Our method consists of comparative analysis of articles about the situation in chosen countries. We compare the solutions about the diagnosis process, preferences to hearing aids and rehabilitation type used in each country and then how the main issues influence on the child growth and the family satisfaction. The results show that the systemic and institutional solutions are different, however the implication of parents' status is the relevant indicator of harmonious child development. The question remains also: how better support the parents’ involvement ? What type of support propose to a child ? Description of the systems of support and education of DHH children will offer an insight into solutions proposed in the selected countries. However, based on the comparisons – the best solutions may be introduced

    Conclusions and research perspectives concerning the system of early-developement support and education provided to hearing impaired children and youth

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    Our description of proposed system solutions in terms of early-development support and education is based on the analysis of submitted articles and personal,international cooperation of editors. The result of such comparisons are general conclusions and proposed postulates, regarding individual components of the system of support and education of children and youth with hearing impairment
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