1,721,005 research outputs found
The "silent" global burden of congenital cytomegalovirus.
No full textSUMMARY
Human cytomegalovirus (CMV) is a leading cause of congenital
infections worldwide. In the developed world, following
the virtual elimination of circulating rubella, it is the commonest
nongenetic cause of childhood hearing loss and an important
cause of neurodevelopmental delay. The seroprevalence of
CMV in adults and the incidence of congenital CMV infection
are highest in developing countries (1 to 5% of births) and are
most likely driven by nonprimary maternal infections. However,
reliable estimates of prevalence and outcome from developing
countries are not available. This is largely due to the
dogma that maternal preexisting seroimmunity virtually eliminates
the risk for sequelae. However, recent data demonstrating
similar rates of sequelae, especially hearing loss, following
primary and nonprimary maternal infection have underscored
the importance of congenital CMV infection in resource-poor
settings. Although a significant proportion of congenital CMV
infections are attributable to maternal primary infection in
well-resourced settings, the absence of specific interventions
for seronegative mothers and uncertainty about fetal prognosis
have discouraged routine maternal antibody screening. Despite
these challenges, encouraging results from prototype vaccines
have been reported, and the first randomized phase III
trials of prenatal interventions and prolonged postnatal antiviral
therapy are under way. Successful implementation of strategies
to prevent or reduce the burden of congenital CMV infection
will require heightened global awareness among
clinicians and the general population. In this review, we highlight
the global epidemiology of congenital CMV and the implications
of growing knowledge in areas of prevention, diagnosis,
prognosis, and management for both low (50 to 70%)-
and high (70%)-seroprevalence settings
A randomized, controlled trial comparing ganciclovir to ganciclovir plus foscarnet (each at half dose) for preemptive therapy of cytomegalovirus infection in transplant recipients
No full textForty-eight patients who provided 2 consecutive blood samples that tested positive for cytomegalovirus DNA by polymerase chain reaction (PCR) were randomized to receive either full-dose ganciclovir ( 5 mg/kg intravenously [iv] twice daily) or half-dose ganciclovir (5 mg/kg iv once daily) plus half-dose foscarnet (90 mg/kg iv once daily) for 14 days. In the ganciclovir arm, 17 (71%) of 24 patients reached the primary end point of being CMV negative by PCR within 14 days of initiation of therapy, compared with 12 (50%) of 24 patients in the ganciclovir-plus-foscarnet arm (P = .12). Toxicity was greater in the combination-therapy arm. In patients who failed to reach the primary end point, baseline virus load was 0.77 log(10) higher, the replication rate before therapy was faster (1.5 vs. 2.7 days), and the viral decay rate was slower (2.9 vs. 1.1 days) after therapy. Bivariable logistic regression models identified baseline virus load, bone-marrow transplantation, and doubling time and half-life of decay as the major factors affecting response to therapy within 14 days. This study did not support a synergistic effect of ganciclovir plus foscarnet in vivo
Human cytomegalovirus (HCMV) replication dynamics in HCMV-naive and -experienced immunocompromised hosts
No full textHuman cytomegalovirus (HCMV) can infect both HCMV-naive and -experienced transplant patients. In this study, the growth rate of HCMV in HCMV-naive hosts (1.82 units/day; 95% confidence interval [CI], 1.44-2.56 units/day) was shown to be significantly faster than the growth rate of virus in HCMV-experienced hosts undergoing recurrent infection (0.61 units/ day; 95% CI, 0.55-0.7 units/day; P93% (95% CI, 89%-98%) is required to eliminate viral growth during infection of HCMV-naive liver transplant recipients, whereas lower efficacy levels are sufficient to reduce the R-0 value to <1 in hosts with prior HCMV immunity
Prospective study of human herpesvirus 6, human herpesvirus 7, and cytomegalovirus infections in human immunodeficiency virus-positive patients
No full textBlood samples from human immunodeficiency virus (HIV)-positive patients were monitored for cytomegalovirus (CMV), human herpesvirus 6 (HHV-6), and HHV-7 by PCR. We detected CMV in 17% of the patients, HHV-6 in 6%, and HHV-7 in 3%. The viral loads of CMV were significantly higher than those of HHV-6 (P = 0.007) or HHV-7 (P = 0.01). Detection of CMV and HHV-6 was associated with low and high CD4 counts, respectively
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
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