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F. Albonico Valenzuela, Manual de Derecho Internacional Privado
No full textF. Albonico Valenzuela, Manual de Derecho Internacional Privado. In: Revue internationale de droit comparé. Vol. 3 N°3, Juillet-septembre 1951. pp. 545-546
ANALYSIS OF MICRORNAS AND GENIC POLYMORPHISMS IN THE DIAGNOSIS OF NEOPLASTIC AND TRANSMISSIBLE DISEASES IN DOGS
Get PDFDuring my PhD, I mainly worked on two different fields of research:
1. Analysis of microRNAs in canine hematopoietic malignancies for diagnostic purposes. MicroRNAs (miRNAs) are a new class of small non-coding RNAs involved in the negative regulation of gene expression. In humans, it has been shown that miRNAs play a key role in the modulation of the innate immune response and in the regulation of normal and neoplastic hematopoiesis. The expression profile of these molecules varies in the different stages of differentiation of the hematopoietic system cellular components and any alteration of these processes is directly associated with dysregulation of one or more miRNAs. The frequency and nature of some of these tumors are similar in dogs and humans. In dog, the studies of hemato-oncology performed to date have shown that the currently used methodologies are not always able to obtain comprehensive information about the staging, grading, immunophenotyping and prognosis of the diseases. This makes miRNAs very attractive as new potential diagnostic and prognostic markers allowing better subclassification of these tumors in dogs. The purpose of the study undertaken in this project was to examine, using stem-loop TaqMan real time RT-PCR, the expression profile of a panel of miRNAs in some hematological malignancies of the dog, such as chronic lymphocytic leukemia (CLL), lymph node lymphoma and splenic lymphoma, in relation to their non cancer tissues. Panels of miRNAs, already known in humans because of their importance in hematopoietic malignancies, have been selected for investigation, according to the information available in the literature and databases, and to their level of conservation in the canine genome. As a preliminary step, for each studied canine neoplasia, an accurate validation of suitable candidate endogenous control (EC) genes for normalization of miRNA expression levels in normal and neoplastic lymphoid tissues was made. This was performed by means of real time RT-PCR followed by statistical analysis using the algorithms NormFinder and geNorm. In all studied lymphoid malignancies, and for each miRNA investigated, a relative quantification (by calculating the delta-delta Ct to the endogenous control gene selected) and an absolute quantification (interpolating its Ct value on standard curves obtained from serial dilutions of an equimolar pool of synthetic miRNAs) was performed after selecting the best housekeeping genes. The results of this study confirm that in dogs, as already shown in humans, there is differential expression of some miRNAs in various hematologic malignancies, suggesting the potential utility of miRNA monitoring as a new diagnostic strategy in canine hematopoietic malignancies. In particular, in lymph node lymphoma samples miR-181a was upregulated in canine T-cell lymphoma and miR-17-5p was upregulated in canine B-cell lymphoma. Moreover, the molar ratio between miR-181a and miR-17-5p clearly distinguished between T-cell and B-cell lymphoma samples. In CLL samples, the molar ratio miR-150/miR-125b was correlated with the immunophenotype. Finally, molar ratio miR-17-5p/miR-155 was correlated with grading in canine splenic lymphoma. Furthermore, in dogs is often difficult to obtain a sufficient number of fresh clinical samples to perform large diagnostic studies. From here the need arises to carry out studies of retrospective nature based on appropriately validated methods of analysis that make possible to analyze archival samples. Therefore, one of the goals of this study was to develop a methodology for extraction and analysis of miRNAs from smears of aspirated lymph node (for the study of lymph node lymphoma) and peripheral blood (for the study of CLL) and from tissue sections fixed in formalin and included in paraffin (for the study of splenic lymphoma). The results obtained during this study confirm the possibility to analyze miRNAs for retrospective studies starting from such archival samples, as the data obtained from these samples are comparable to those obtained from fresh samples.
2. High Resolution Melting Analysis (HRMA) of genic polymorphisms for diagnostic purposes. High Resolution Melting (HRM) analysis is a new, post-PCR analysis method used for identifying genetic variation in nucleic acid sequences. Simple and fast, this method is based on DNA melting (dissociation) curve techniques and is enabled by the recent availability of improved double-stranded DNA (dsDNA)–binding dyes along with next-generation real-time PCR instrumentation and analysis software. HRM analysis can discriminate DNA sequences based on their composition, length, GC content, or strand complementarity. Accordingly, HRMA allows the detection of multiple types of variations in DNA sequences such as single base changes, insertions, deletions and duplications. In this work this new methodology was utilized as a successful rapid diagnostic technique for the evaluation of the resistance to fluoroquinolones in Staphylococcus pseudintermedius isolates from canine clinical samples, and for the detection and discrimination of Dirofilaria immitis and Dirofilaria repens in canine peripheral blood
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Enhanced diagnostic protocol to identify E.coli VTEC from milk filters
Get PDFThe EHEC (enterohemorrhagic E. coli) are a subgroup of VTEC with strong pathogenicity. The most well-known EHEC serotype is E. coli O157:H7, which has been implicated in many large outbreaks of deadly human diseases. However, EHEC strains of other serotypes have increasingly been implicated in sporadic cases and outbreaks of serious illness in humans, e.g., serotypes O26, O45, O103, O111, O121 and O145. Epidemics studied from 1982 to date have shown that ruminants, and in particular bovine, appear almost always involved in the transmission of these bacteria to humans through direct or indirect fecal contamination of foods. Unpasteurized milk and milk products are considered minor, but important sources of infection. The possible ways to the entrance of VTEC in milk are fecal contamination and mammary excretion during E.coli mastitis. Between the two ways, the first is considered much more frequent in practice, but it cannot be excluded that a small part of EHEC found in milk resulting from mammary gland, as reported.
Previous investigation suggested that milk filters used in milking machines could be a useful control point to identify the presence of EHEC in dairy herds. However, conventional methods to identify the presence of EHEC have a poor sensitivity due the high content of fecal bacteria of these filters.
In order to set up a monitoring scheme to identify herds at risk, we developed and tested a diagnostic protocol involving VIDAS® UP E.coli serogroups (ESPT) which is a method using phage recombinant proteins for the immuno-concentration (IC) of E.coli serogroups O157, O26, O103, O111, O145, O45 and O121 from food, multiplex PCR and high resolution melting analysis (HRMA).
Practically, bulk tank milk or washing solution obtained from milk filters after stomacher mixing were analyzed by Vidas ESPT. After incubation, the solution obtained was analyzed by multiplex PCR based on serotype-specific primers coding for O-antigen regions of the seven major VTEC serogroups available in literature. If PCR was positive for any of the seven serogroups, a HRMA-based protocol to detect virulence-predictive SNPs, as discovered by Norman et al., 2012, was applied to confirm the presence of a EHEC strain.
The protocol was preliminary validated by inoculation of milk and milk filters with a known concentration of the seven EHEC serotypes (O26, O45, O103, O111, O121, O145, O157). The results confirmed that this protocol was able to identify as low as 101 UFC in both milk and milk filters.
The protocol applied to milk and milk filters obtained from 70 dairy herds allow to identify 2 EHEC from milk and 17 from milk filters for one or more of the EHEC serogroups considered.
The proposed protocol confirmed to be useful in detecting the presence of EHEC and that milk filters are an important critical control point to identify herd at risk
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
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