1,720,976 research outputs found
Human papillomavirus - associated head and neck squamous cell carcinomas in North-East Italy
Get PDFBackground: Specific oncogenic types of human papillomaviruses (HPV), most frequently HPV16, are causally associated with a subset of head and neck squamous cell carcinomas (HNSCC). HPV DNA associated tumors appear to be heterogeneous in prevalence over time and geographically, in the oncogenic activity (direct and indirect viral markers) and clinical behavior. However, it remains unclear which biomarkers can reliably determine which HNSCC are truly driven by HPV transformation.
Aims: In the present thesis, the first aim was to determine the prevalence of the truly HPV-associated HNSCC tumors in North-East Italy. The second aim, was to investigate the association of HPV DNA positivity with other viral (viral load, oncoE6 protein, HPV antibodies) and cellular (p16INK4a, pRb) markers. The third aim, was to evaluate the prognostic significance of HPV-association tumors for clinical outcome (i.e. survival).
Materials and Methods: Overall, 247 fresh frozen and 53 (21%) formalin-fixed paraffin-embedded (FFPE) tumor tissue biopsies and 102 (41%) sera were collected from 247 newly detected HNSCC patients from North-East Italy. Clinical parameters for each patient were obtained from the clinical database.
HPV DNA was determined by polymerase chain reaction (PCR) with consensus MY09/MY11 primers and Restriction Fragment Length Polymorphism (RFLP) analysis and/or BSGP5+/6+-PCR/Multiplex Papillomavirus Genotyping (MPG) capable of detecting all known 51 mucosal HPV types.
The HPV DNA+ tumor tissues were further analyzed for i) viral load by HPV16 qPCR and quantitative BSGP5+/6+-PCR/MS; ii) detection of HPV E6*I transcripts by RT-PCR; iii) expression levels of cellular protein p16INK4a and pRb by IHC; and iv) presence of HPVE6 protein for types 16 and 18 by the commercial OncoE6TM Oral Test; Antibodies to HPV early and late proteins of the eight most frequent high-risk HPV types were determine din all available sera by bead-based multiplex serology.
Results: Overall, HPV DNA+ was 8.5% (21/247), type 16 was detected in 95% (20 cases) and type 58 in 5% (1 case). No multiple infections were detected. The HPV RNA+ was 6% (14/244). Oropharynx was the site with the highest HPV prevalence by DNA (27%) and RNA (20%). In the other anatomic sites, HPV prevalence was < 8%.
Among the HPVDNA+ RNA+ tumors, i) 93% of the HPV16+ tissues (13/14) showed high viral load; ii) 60% (6/10) showed both up-regulation of p16INK4a and down-regulation of pRb; iii) and in 100% (8/8) HPV16 E6 oncoprotein was detected. All sera of 7 HPV-driven tumors showed strong positive antibody reactions with HPVE6 and E7 proteins, 6 for type 16 and 1 for type 58, type-concordant with the related tumor. Another single serum HPV16 DNA+ in the tumor, showed positivity for all early HPV16 proteins suggestive of an HPV-driven tumor. Kaplan-Meier analyses for the oropharynx showed a trend for better survival in the HPV-associated group than in the HPV negative ones.
Conclusions: A low HPV prevalence was found in HNSCC of the population living in the North-East of Italy. Oropharynx was the preferential site for HPV infection while the HPV prevalence in the other anatomic sites appeared negligeable. We observed that the HPVDNA+ RNA+ samples showed a good correlation with the other markers like high viral load, presence of the E6 oncoprotein, and HPVE6 and E7 seromarkers. In contrast to recent reports we did not find a good correlation between HPVDNA+ RNA+ and the up-regulation of p16INK4a and down-regulation of pRb. Survival analyses showed a better prognosis in the HPV-driven patients with tumors occurring in the oropharynx
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
Oral human papillomavirus and human herpesvirus-8 infections among human immunodeficiency virus type 1-infected men and women in Italy.
No full textBackground: Oral human papillomavirus (HPV) and human herpesvirus-8 (HHV8) infections are sexually transmitted and respectively associated with the development of oropharyngeal carcinoma and Kaposi sarcoma. The aim of the study was to evaluate HPV prevalence and its possible correlation with HHV8 oral shedding, in relation to sex, human immunodeficiency virus (HIV) behavioral risk factor, and immune function.
Methods: The study population comprised 100 HIV-infected individuals divided into 3 groups: (1) 38 men who have sex with men (MSM), (2) 24 heterosexual men, and (3) 38 women. DNA was obtained from cells of unstimulated whole saliva. Human papillomavirus sequences were searched for by polymerase chain reaction (PCR) with MY09/MY11 primers or by nested PCR with GP5+/GP6+ primers as the second step. Typing was accomplished by restriction fragment length polymorphism analysis or by direct sequencing or by reverse line blot. Human herpesvirus-8 sequences were detected and quantified by nested PCR and real-time PCR, respectively.
Results: Oral HPV infection was present in 37 (prevalence, 37%) of 100 (13 with high-risk and 24 with low-risk types) patients; the most frequent types were HPV16, HPV6, HPV10, HPV61, HPV66, and HPV83. Human herpesvirus-8 DNA was detected in 46 (46%) of 100 subjects. Both infections had the highest prevalence among MSM and the lowest among women; women had a lower prevalence of high-risk HPV types than did both male groups (P = 0.05). An inverse correlation was observed with concomitant oral HHV8 infection (P = 0.007).
Conclusions: High prevalence of oral HPV and HHV8 infections was observed; MSM had the highest figures, despite better control of HIV infection
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
Age and geographic variability of human papillomavirus high-risk genotype distribution in a large unvaccinated population and of vaccination impact on HPV prevalence
No full textBackground: The prevalence of infections with human papillomavirus (HPV) specific genotypes differs by age and areas. Knowledge of these differences will help predicting how prophylactic HPV vaccination and screening program could best be integrated.
Objectives: To investigate variations in the HPV distribution between areas and ages in Italy and the impact of vaccination on HPV prevalence.
Study design: 37,367 women aged 25-60 years who attended cervical screening in eight different areas in Northern and Central Italy were tested for HPV infection with the high-risk hybrid capture (hr-HC2) assay. hr-HC2 positive samples were genotyped by an intensive integrated strategy.
Results: hr-HPV types were detected in 79.1% of HC2 positive women. HPV16 was the most frequent type, followed by HPV31, HPV18 and HPV56. A statistically significant variability in HPV type distribution between centres (overall Y,,284df 195.86 p< 0.001) was observed. No significant overall difference in the HPV type distribution was observed in the age groups 25-34, 35-44 and 45-60 years. Considering cross-protection, overall 57.6% (95%CI 56.0-59.3) of all infections by hr-HPV types was preventable by vaccination with the bivalent vaccine and 49% (95%CI 46.9-51.1) with the quadrivalent vaccine. The variability between centres was statistically significant with both bivalent (z27df = 43.8, p <0.0001) and quadrivalent vaccine (Z27df = 32.9, p <0.0001).
Conclusions: We observed differences in HPV genotype distribution according to centres but not to age. Results suggest that the higher proportion of HPV16/18 related high grade CIN in younger women could be the result of faster progression and not of earlier infection by these types. (C) 2014 Published by Elsevi
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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