1,720,976 research outputs found
Hylotelephium telephium (L) H. Ohba leaves juice improves herpetic lesions: new findings from in vitro investigations
No full textThe efficacy of Hylotelephium telephium (L.) H. Ohba (better known with its botanical synonym Sedum telephium L.) fresh leaf juice in the treatment of Herpes labialis wounds has been reported in traditional medicine in particular in Central regions of Italy; however, scientific insights are missing and the mechanism of action is not well understood. Aim of this study was to investigate the biological properties of S. telephium that underlie its ability to heal herpetic lesions. S. telephium fresh leaf juice (STJ) was analysed to obtain phytochemical information and tested in vitro to evaluate its antiviral activity against HSV-1 in Vero cells, then, according to computational predictions, immunomodulatory properties of STJ in human lympho-monocytes (PBMC), as well as its effect on cell viability in human keratinocytes (HaCaT cells), were also evaluated. Our results, at least in part, may explain the improvement of herpetic lesions empirically observed in patients treated with STJ: such improvement was not related to direct anti-viral effect of the juice but to its experimentally confirmed activity as cell viability booster and immunomodulatory agent
Parvovirus B19 in Rheumatic Diseases
Full text linkParvovirus B19 (B19V) is a human pathogen belonging to the Parvoviridae family. It is widely diffused in the population and responsible for a wide range of diseases, diverse in pathogenetic mechanisms, clinical course, and severity. B19V infects and replicates in erythroid progenitor cells (EPCs) in the bone marrow leading to their apoptosis. Moreover, it can also infect, in an abortive manner, a wide set of different cell types, normally non-permissive, and modify their normal physiology. Differences in the characteristics of virus-cell interaction may translate into different pathogenetic mechanisms and clinical outcomes. Joint involvement is a typical manifestation of B19V infection in adults. Moreover, several reports suggest, that B19V could be involved in the pathogenesis of some autoimmune rheumatologic diseases such as rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA), systemic sclerosis (SSc), systemic lupus erythematosus (SLE), or vasculitis. This review provides basic information on the B19 virus, highlights characteristics of viral infection in permissive and non-permissive systems, and focuses on recent findings concerning the pathogenic role of B19V in rheumatologic diseases
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
Respiratory viral infections in ICU patients: comparison of upper and lower respiratory samples
No full textRespiratory viruses cause many diseases, from mild to severe illnesses, and contribute significantly to morbidity and mortality worldwide. Different viruses can establish respiratory tract infections, they belong to the Orthomyxoviridae, Coronaviridae, Picornaviridae, Paramyxoviridae, Adenoviridae, Parvoviridae and in immunocompromised patients Herpesviridae families. Altogether, the etiologic diagnosis of respiratory viral infections has been underestimated so far. In patients with predisposing conditions the outcome of these infections can be more severe, sometimes requiring hospitalization, even in intensive care units (ICU), because of the development of pneumonia and acute respiratory distress syndrome (ARDS). For these patients, in particular, rapid diagnosis is essential. In addition, in ICU patients the significance of the detection of some members of Herpesviridae family, like HSV1, CMV and EBV, is controversial. The aim of this study was to clarify the prevalence of respiratory viruses and herpesviruses, and their role in ICU patients. Large part of this study was devoted to the development of diagnostic assays able to accurately characterise respiratory viruses quickly and at the lowest costs. Viral detection was performed in both upper and lower respiratory samples in order to compare the viral populations in these two compartments and, possibly, to draw informations concerning the role of the infection in severe cases.
Four duplex RT real-time PCRs, using EvaGreen fluorescent dye, were developed to identify and characterize the main respiratory RNA viruses directly from clinical samples. A duplex was performed to detect influenza A and influenza B viruses; a second duplex was performed to detect PIVs belonging to Respirovirus genera (PIV1 and PIV3) and RSV; the viruses target for the third duplex PCR were PIV type 2 and hMPV; and a fourth duplex was performed to detect CoV I and EV/RV.
The results of the duplex real-time PCRs were confirmed by sequencing positive samples and by comparison with other assays, including commercial, validated, assays, which gave similar results. A total of 156 clinical samples from upper and lower respiratory tract of 58 adult patients hospitalized in ICU were analysed. In 80% of positive adult patients influenza A viruses were detected, in 8% influenza B viruses and rhinovirus/enterovirus and in 4% metapneumoviruses. In particular in all ICU adult patients positive for influenza A or B viruses, the virus was demonstrated in both upper or lower respiratory tract samples. For an adult patient positive for RV/EV, the virus was detected in both samples; while for another only the upper respiratory tract sample was positive. Only one upper respiratory tract sample from one patient was positive for hMPV. The results obtained in this study were in agreement with other published studies that showed influenza virus as the most common virus detected in ICU patients, followed by rhinoviruses.
Furthermore, three nested PCRs were developed to detect herpesviruses (CMV, EBV and HSV1). To understand better the role of these viruses in ICU patients all herpesviruses positive clinical samples obtained by nested-PCRs were further analyzed by quantitative real-time PCRs.
Altogether, 37 of 58 (about 64%) patients were positive for one or more herpesviruses.
EBV was detected in 25 patients of 58, either as single or mixed infection; CMV and HSV1 were detected in 15 patients either as single or mixed infection. Mixed infections were not rare.
In general, for EBV viral load in TS samples was higher than in BAL samples. These results could suggest a possible viral contamination of the lower respiratory tract from mouth or throat or both. In one case EBV DNA was detected in the BAL only in two successive specimens at a low viral load (103-104). Further monitoring should be performed to better understand these data.
In this study CMV was detected as single infection only in two patients. Regarding CMV association with pneumonia, the average values of viral load reported in literature vary; however a viral load in BAL samples, between 4,6x104 and 5x105 copies number/ml, has been proposed as a threshold for the diagnosis of pneumonia. None of the patients analysed in this study had a viral load within this range only in BAL sample.
HSV1 was detected in 15 patients of 58 as single or mixed infection. In general, all patients HSV1 positive had high viral load in TS and in BAL samples (average value 106). In one patient only the detection of a high viral load in the BAL in absence of viral DNA in the TS could suggest an involvement of this virus in the lower respiratory tract disease.
The assays described could be particularly useful to screen a large number of patients for epidemiological studies and to assess the prevalence in the lower and upper respiratory tract of ICU patients with, regarding CMV, EBV and HSV1, the ultimate goal to understand the clinical significance of this phenomenon.
The possible contribute of the use of the NGS to the knowledges of the viruses involved in upper and lower respiratory tract infections was also studied preliminary in a small number of ICU patients. Nextera-XT protocol to MiSeq platform has been used
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
Parvovirus B19 activates in vitro normal human dermal fibroblasts: a possible implication in skin fibrosis and systemic sclerosis
Full text linkFibrosis is the most characteristic pathological hallmark of SSc, a connective tissue disease characterized by vascular and immunological abnormalities, inflammation and enhanced extracellular matrix production, leading to progressive fibrosis of skin and internal organs. We previously demonstrated that parvovirus B19 (B19V) can infect normal human dermal fibroblasts (NHDFs) and that B19V persists in SSc fibroblasts. In this study, we investigated whether parvovirus B19V is able to activate in vitro NHDFs and to induce in these cells some phenotypic features similar to that observed in the SSc fibroblasts
- …
