1,720,973 research outputs found
Caratterizzazione molecolare delle variazioni di sequenza del gene hIDS in pazienti affetti da sindrome di Hunter
Full text linkHunter syndrome or mucopolysaccharidosis type II (MPS II) is an X-linked disorder caused by the deficienct activity of the lysosomal enzyme iduronate-2-sulfatase (IDS) causing accumulation of partially degraded dermatan and heparan sulfates in various tissues and progressive impairment of function.
Hunter syndrome is a disease with multiorgan and multisystem involvement that shows a complete spectrum of phenotypes from attenuated to intermediate and severe.
The diagnosis is based on the collection of clinical data, on dosage of urine GAG levels and on mutational analysis of the hIDS gene.
Until recently, the management of Hunter syndrome has been palliative and focused on the treatment of signs and symptoms. Enzyme replacement therapy (ERT) with recombinant human iduronate-2- sulfatase (idursulfase) has lately been introduced. ERT has been shown to improve many of the sign and symptoms and overall wellbeing of patients with MPS II.
The IDS locus, located on Xq27.3-q28, spans a region of 24 kb and contains 9 exons. At 20 kb telomeric and in opposite orientation to the IDS gene, a pseudogene, IDS2, containing sequences homologous to exons 2, 3 and introns 2, 3, 7 is present. To date, more than 330 different mutations have been identified in the IDS gene: 89% being small variations, while 11% major structural alterations. The most common rearrangement is an intrachromosomal homologous recombination event between IDS and IDS-2 sequences.
Fifteen unrelated patients were analyzed in this study, 11 Italian and 4 Brazilian. Among the 15 cases analyzed 16 sequence variations were detected: 12 point mutations or small deletions, one medium size deletion, 2 large deletions, a recombination associated to a deletion. Among them 9 were novel sequence variations and 2 were de novo mutations as the mother didn’t result carrier.
The rarity of the disease and the fact that most mutations are private make evalutation of the genotype-phenotype correlation very difficult.
Among the 15 patients described, 9 showed a severe form of the pathology, 4 an intermediate one and 2 were mild. A genotype-fenotype relationship was attempted for each case. The complete absence of functional enzyme caused by total or partial gene deletion or by gene-pseudogene rearrangement seemed to result in a severe form in the cases analyzed. Genotype-phenotype correlation for point mutations was more complex and a specific discussion was necessary for each sequence variation.
Molecular analysis is a valid method to support clinical and biochemical diagnosis confirming the results obtained from the previous approaches. Gene analysis is the only secure method to identify female carriers among a patient’s relatives and therefore it is essential in genetic counselling. Furthermore, it is useful in prenatal diagnosis in order to detect the mutation carried by a heterozygote mother
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
Mucopolysaccharidosis Type II: One Hundred Years of Research, Diagnosis, and Treatment
Full text linkMucopolysaccharidosis type II (MPS II, Hunter syndrome) was first described by Dr. Charles Hunter in 1917. Since then, about one hundred years have passed and Hunter syndrome, although at first neglected for a few decades and afterwards mistaken for a long time for the similar disorder Hurler syndrome, has been clearly distinguished as a specific disease since 1978, when the distinct genetic causes of the two disorders were finally identified. MPS II is a rare genetic disorder, recently described as presenting an incidence rate ranging from 0.38 to 1.09 per 100,000 live male births, and it is the only X-linked-inherited mucopolysaccharidosis. The complex disease is due to a deficit of the lysosomal hydrolase iduronate 2-sulphatase, which is a crucial enzyme in the stepwise degradation of heparan and dermatan sulphate. This contributes to a heavy clinical phenotype involving most organ-systems, including the brain, in at least two-thirds of cases. In this review, we will summarize the history of the disease during this century through clinical and laboratory evaluations that allowed its definition, its correct diagnosis, a partial comprehension of its pathogenesis, and the proposition of therapeutic protocols. We will also highlight the main open issues related to the possible inclusion of MPS II in newborn screenings, the comprehension of brain pathogenesis, and treatment of the neurological compartment
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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