1,721,002 research outputs found
MPXV infection impairs IFN response but is partially sensitive to IFN-γ antiviral effect
No full textThe recent outbreak of monkeypox virus (MPXV) has caused global concern. How the virus evades the interferon (IFN) response is still poorly understood. We analyzed type I/II IFN (IFN-I/II) expression in clinical samples from MPXV-infected patients and measured IFN-I kinetics in MPXV-infected cells. We also evaluated the anti-MPXV activity of IFN-I/II in A549, HeLa and Vero-E6 cell lines. IFN-I/II mRNA expression was detected in skin lesions, anal swabs, nasopharyngeal samples and peripheral blood mononuclear cells (PBMC), with the highest levels in skin lesions (p < 0.05). High MPXV DNA levels in clinical samples were associated with increased IFN-I levels. In vitro, MPXV infection induced a peak of IFN-I between 48 and 72 h post-infection (p < 0.01). Pre-treatment of the A549, HeLa and Vero-E6 cells with high concentrations (≥ 100,000 International Unit, IU/ml) of IFN-α and IFN-ω did not inhibit or had little effect on MPXV replication, while IFN-β moderately reduced MPXV replication by 2.7–1.5 log10 at 100,000 IU/ml. In clinical samples there was a trend for elevated levels of IFN-γ in association with lower MPXV load and in vitro IFN-γ (3,600 IU/ml) strongly reduced viral titers by 3.4–1.6 log10. There were no significant differences in expression of select IFN-stimulated genes (ISGs) in MPXV infection in vitro. This study shows that MPXV delays IFN-I induction and inhibits expression of selected ISGs in vitro and is associated with an IFN-I resistance phenotype in vivo. However, MPXV is less resistant to IFN-γ in vivo and is sensitive to IFN-γ treatment in vitro, suggesting a potential therapeutic role for IFN-γ
High frequency of neutralizing antibodies to type I Interferon in HIV-1 patients hospitalized for COVID-19
No full textThe presence of anti-IFN neutralizing antibodies (NAB) has been reported in critically ill COVID-19 patients. We found that 87.5% (7/8) of HIV-1 patients co-infected with SARS-CoV-2 had serum anti-IFN-I NAB against IFN-α subtypes, IFN-β and/or IFN-ω. Anti-IFN-I NAB were also detected in oropharyngeal samples. Patients with NAB were males, and those with high serum anti-IFN-α/ω NAB titer had severe illness and exhibited reduction in the expression of IFN-stimulated genes. Thus, high titer of anti-IFN-α/ω NAB may contribute to the greater severity of COVID-19 in HIV-1 infected patients
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
Insights into the role of innate immunity in cervicovaginal papillomavirus infection from studies using gene deficient mice
Get PDFWe demonstrate that female C57BL/6J mice are susceptible to a transient lower genital tract infection with MmuPV1 mouse papillomavirus and display focal histopathological abnormalities resembling human papillomavirus infection. We took advantage of strains of genetically deficient mice to study in vivo the role of innate immune signaling in control of papillomavirus. At 4 months, we sacrificed MmuPV1-infected mice and measured viral 757/3139 spliced transcripts by TaqMan RT-PCR, localization of infection by RNAscope in situ hybridization, and histopathological abnormities by H&E stain. Among mice deficient in receptors for pathogen-associated molecular patterns, MyD88-/- and STING-/- mice had 1350 and 80 copies of spliced transcripts/μg RNA, respectively, while no viral expression was detected in MAVS-/- and Ripk2-/- mice. Mice deficient in an adaptor molecule, STAT1-/-, for interferon signaling had 46,000 copies/μg RNA. Among mice with targeted deficiencies in the inflammatory response, IL-1R-/- and caspase-1-/- mice had 350 and 30 copies/μg RNA, respectively. Among mice deficient in chemokine receptors, CCR6-/- mice had 120 copies/μg RNA, while CXCR2-/- and CXCR3-/- mice were negative. RNAscope confirmed focal infection in MyD88-/-, STAT1-/- and CCR6-/- mice but was negative for other gene deficient mice. Histological abnormalities were seen only in the latter mice. Our findings and the literature support a working model of innate immunity to papillomaviruses involving activation of a MyD88 dependent pathway and IL-1 receptor signaling, control of viral replication by interferon-stimulated genes, and clearance of virus-transformed dysplastic cells by action of the CCR6/CCL20 axis.IMPORTANCE Papillomaviruses infect stratified squamous epithelia and the viral life cycle is linked to epithelial differentiation. Additionally, changes occur in viral and host gene expression and immune cells are activated to modulate the infectious process. In vitro studies with keratinocytes cannot fully model the complex viral and host response and do not reflect the contribution of local and migrating immune cells. We show that female C57BL/6J mice are susceptible to a transient papillomavirus cervicovaginal infection, and mice deficient in select genes involved in innate immune responses are susceptible to persistent infection with variable manifestations of histopathological abnormalities. The results of our studies support a working model of innate immunity to papillomaviruses, and the model provides a framework for more in depth studies. A better understanding of mechanisms of early viral clearance and development of approaches to induce clearance will be important for cancer prevention and treatment of HPV-related diseases
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
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