1,720,995 research outputs found
Genus-specific salivary proteins as serological markers of human exposure to mosquito bites
No full textSalivary proteins injected by mosquitoes into hosts play an essential blood feeding role by counteracting hemostasis, inflammation and immunity; however, they also elicit an immune response with production of anti-saliva antibodies. Several experimental observations support the concept that this antibody response to saliva may be exploited to assess human exposure to vectors and, therefore, may represent a helpful tool to evaluate disease risk and efficacy of anti-vector control interventions. In the last years we analyzed the salivary repertoires of Anopheles gambiae, Aedes aegypti and Aedes albopictus and identified genus-specific salivary proteins, i.e. proteins that are found in Anopheles but not in Aedes or Culex saliva, and viceversa. These proteins, if immunogenic, could be ideal markers of exposure to mosquito vectors. Based on this information we have recently shown that the antibody response to the Anopheles-specific salivary protein gSG6 is a promising marker to evaluate human exposure to Afrotropical malaria vectors.
The wide spread of the tiger mosquito in Italy/Europe, as well as the recent Chikungunja and Dengue cases in Italy and France, highlighted the need for both effective control interventions and tools to evaluate their efficacy. In this respect the development of recombinant salivary antigens as markers of human exposure to Ae. albopictus could be extremely useful. Such a tool may allow to directly monitor, through simple serological measures, the effect of mosquito control interventions on human exposure to Aedes mosquito bites. To this end we selected seven different Ae. albopictus salivary proteins (which are absent in the saliva of Anopheles and Culex species) and cloned corresponding cDNAs in suitable E. coli expression vectors. Optimization of conditions for their expression and purification is currently in progress
Detoxification of aromatic aldehydes in the archaeon Sulfolobus solfataricus is regulated by a Mar-like transcription factor.
No full textINTRODUCTION: Investigation of mechanisms underlying transcriptional regulation of Sso2536, encoding for an alcohol dehydrogenase gene (adh) in the crenarchaeon S. solfataricus has shown an active 5’ flanking region responsive to physiologically relevant DNA binding proteins. In particular, one DNA binding protein, Bald16 (Sso1352), has been identified whose levels are higher when cells are grown in the presence of the toxic benzaldehyde, substrate of the ADH enzyme; it has been proposed that this protein could act as a transcriptional activator triggering adh expression to protect cells from an environmental stress due to phenolic-derived aldehydes. Bald16 encodes for a putative transcriptional regulator, which has a bacterial homologue belonging to the Mar (Multiple Antibiotic Resistance) family of regulators involved in the control of gene expression of aromatic compound metabolism and antibiotic resistance. To better investigate the molecular mechanisms underlying transcriptional regulation in S.solfataricus, with greater attention with respect to defense response upon chemical stress, we analyzed the expression of the bald16 gene in the presence of aromatic aldehydes. Furthermore, recombinant Bald16 has been obtained in E. coli and characterized for its DNA binding activity.
MATERIALS AND METHODS S. solfataricus cultures were grown in different conditions among which DSM182 medium supplemented with 1 mM benzaldehyde, 1mM veratrylaldehyde, 0,35 mM cynnamaldehyde and harvested at exponential or stationary phase. mRNA and crude extracts were prepared according to conventional procedures to perform Northern and Western blot analyses, respectively. Recombinant Bald16 was obtained by PCR amplification of the Sso1352 ORF and cloning in the pTrc99A vector and purified by thermal precipitation and three chromatographic steps. Functional analysis has been performed essentially by band shift analysis and DNAseI footprinting using synthetic double stranded oligonucleotides designed on the sequences of the adh or bald16 promoter and DNA fragments prepared by endonuclease restriction of the 5’ flanking regions upstream of the adh or bald16 gene.
RESULTS Transcriptional analysis of the Bald16 gene allowed the identification of a new a mar-like locus in S. solfataricus composed of a putative multidrug transporter and the transcriptional regulator downstream (Sso1351, Sso1352). The genes are transcribed as a polycistronic unit whose expression is sensitive to the addition to the cell growth medium of different aromatic aldehydes. The gene encoding for the transcriptional regulator, has been overexpressed in E. coli and the recombinant protein purified to homogeneity. The protein is indeed a DNA binding protein, which binds site-specifically to both the adh and Bald16 promoters, reasonably strengthening the hypothesis of a coordinate expression in response to stress determined by phenolic-derived materials
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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