1,720,964 research outputs found
Diagnosis of congenital cytomegalovirus infection by detection of viral DNA in dried blood spots
No full textBackground: The reference method of cytomegalovirus (CMV) isolation from urine or saliva is not a feasible routine technique for all newborns,- and laboratory -diagnosis -of- this- infection-would be useful- -both for--epidemiological purposes and to enable prompt institution of adequate measures to identify and correct late sequelae. Extraction and amplification of viral DNA from dried blood spots (DBS) collected from babies in the first days of life during routine screening for genetic and metabolic disorders has been proposed for the early diagnosis of viral congenital infections.
Objectives: To test the method for CMV DNA extraction from DBS and to evaluate the results obtained in newborns with and without a diagnosis of congenital infection based on viral isolation from urine and or saliva at birth.
Study design: DBS from Guthrie cards collected in babies who underwent virological tests for CMV infection were tested for CMV DNA by observers blinded to the virological results. DNA was extracted from DBS both in water and in cell culture medium according to Shibata et al. with minor modifications. The products of nested polymerase chain reactions (PCR) amplifying two regions in the 1E1 and gp58 genes were detected by agarose gel electrophoresis. Strict control measures were adopted to avoid carryovers and contaminations.
Results: DBS from the eight symptomatic and 11 asymptomatic congenitally infected babies were positive when extraction was performed in medium, whereas extraction in water failed to identify two of the asymptomatic cases. The results obtained with the two extraction methods agreed in the remaining cases; the 71 CMV negative control babies were negative and two out of 21 cases of supposed postnatal infection were diagnosed as congenital on the basis of a positive DBS. All positive cases were identified by gp58 PCR but only slightly over half of them by 1E1 PCR. Extraction in medium was more efficient than in water.
Conclusions: The method of CMV DNA extraction in medium followed by amplification of the gp58 region showed 100% sensitivity and specificity compared with isolation in cell culture. Therefore, we propose this procedure to diagnose congenital CMV infection at birth and also later
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
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
IN VITRO EVALUATION OF THE ANTIVIRAL ACTIVITY OF THE ASPIRIN / DIETHYL ETHER (ADE) MIXTURE FOR HERPES ZOSTER AND POST-HERPETIC NEURALGIA
No full textAim of investigation. The efficacy of topical aspirin/diethyl ether mixture in the treatment of acute herpetic neuralgia and post-herpetic neuralgia had been established in two, previous open-label and placebo- controlled studies (De Benedittis et al., Pain 48: 383-390 , 1992; De Benedittis & Lorenzetti,Abstracts, 7th World Congress on Pain , Paris, p. 186 , IASP Publications, Seattle,1993). Moreover, a striking reduction of the percentage of acute herpetic neuralgia patients developing post-herpetic neuralgia had been observed in the treated groups as compared with the disease natural history reported in the literature. Since this action could be assumed as an indirect, objective indicator of treatment efficacy in controlling the severity of Herpes Zoster, the aim of the present study was to evaluate the in vitro activity of the ADE mixture on both viral particles and replicative cycle of varicella-zoster virus (VZV) and herpes simplex virus type l(HSV1) as the Herpesviridae prototype virus.
Method. Suspensions of HSV1 were incubated alternatively with Aspirin 400 mM, diethyl ether and the mixture (1:1, v/v) of the two; the reduction of the viral titer was assessed by the plaque reduction assay. The activity on viral replication was checked on human fetal fibroblasts (MRCS) infected with VZV and on african green monkey kidney cells (VERO) infected with HSV1, and the 50% inhibiting dose (ID50) was calculated.
Results. A 100% reduction of the suspensions titer was obtained both by the mixture and the ether; no effect was observed following the incubation with aspirin alone. An inhibition of the replicative cycle by aspirin was observed. The ID50 resulted in the range (1-3 mM) of the plasma concentrations attained in the clinical treatment of inflammation.
Conclusions. Preliminary data indicate an antiviral activity of aspirin which is exerted at a replicative level but not on the viral particle. The antiviral effect might be due to inhibition by aspirin and Na salicylate of the transcription factor NF-kB (Kopp & Gosh, Science, 128: 432-435, 1994). Further studies aimed at assessing the aspirin concentrations attained by topical use and the viral replication stage of the inhibition are irrprugress-.-
CYTOMEGALOVIRUS E PAZIENTE HIV+: IMPEGNO DEL LABORATORIO DI DIAGNOSTICA VIROLOGICA
No full textObiettivo: valutare l'impatto delle infezioni da cytome galovirus in soggetti con infezioni da HIV sulla base del- le richieste di accertamento diagnostico di laboratorio. Materiali e Metodi: sono stati analizzati i dati relativi all'attivita diagnostica svolta nel 1994 per l'accertamen¬to delle infezioni da CMV in circa 1000 pazienti HIV+ rico verati in 4 Ospedali lombardi. Si sono considerate esclusi vamente le indagini virologiche svolte su campioni di leu¬cociti di sangue periferico (PBL). Tali prove sono consistite nella determinazione quantitativa di antigenemiapp65 e viremia p72 e nella ricerca di virus infettante tramite prove di isolamento in coltura cellulare.
Risultati: complessivamente su 981 casi esaminati nel 1994 428 soggetti (43%) sono risultati positivi per CMV in alme no un'occasione (media: 2 campioni positivi/paziente). La febbre 6 stato it dato clinico segnalato piia frequentemen¬te (1478 invii su 2076) da solo o in accompagnamento ad al tri problemi clinici. Un quarto circa dei campioni 6 stato inviato per it controllo della terapia. La determinazione
della antigenemia 6 risultata positiva nel 40% dei campio¬ni esaminati e nella quasi totality (99%) dei positivi. Conclusioni: le indagini virologiche svolte hanno consenti to di fornire al clinico indicazioni di infezione in poco meno della meta dei casi esaminati e di effettuare it moni toraggio della terapia nella quota di pazienti trattati. Questi dati sono di particolare rilievo in termini di orga nizzazione e di impegno del personale quando si tenga pre¬sente che i risultati sono stati disponibili entro 24 ore dall'invio dei campioni, per 5 giorni alla settimana. Solo a queste ultime condizioni si ritiene che it lavoro diagno stico possa avere un impatto significativo sulla gestione
del paziente
CIRCULATING CMV-INFECTED ENDOTHELIAL CELLS (CCIC) IN AIDS PAITIENTS WITH CMV RELATED SYMPTOMS
No full textOBJECTIVE: Tp assess the frequency of the presence and th with laboratory findings and clinical conditions of CCIC patients with CMV infection.
METHODS: CMV infection routine diagnosis (viral isolation and determination of pp65 antigenemia and p72 viremia) was performed on 1737 blood samples (buffy-coat cells) from 450 HIV infected patients. Ficoll separation of mononuclear cells and PCR amplification of a IE1 gene region of CMV was performed on selected cases.
RESULTS: CCIC were found in 30 samples from 21 patients: Eleven specimens were positive in the course of anti-CMV therapy. All positive samples were also pp65, p72 and isolation positive. Ficoll separation allowed a greater number of CCIC to be found. PCR was positive in all but one of the CCIC positive samples.
DISCUSSION: CCIC were not frequently found; their systematic search in the mononuclear cell fraction could contribute to the understanding of their role
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