1,720,982 research outputs found
Laboratory diagnosis of Neisseria gonorrhoeae pharyngeal and rectal infections by culture and real-time polymerase chain reaction (RT-PCR)
No full textObjectives: Nucleic acid amplification testing (NAAT) has become the preferred method to detect Neisseria gonorrhoeae infections, but no commercial tests have been cleared so far for use with rectal or pharyngeal swab samples, despite anal and oral sex practices are common, in particular for MSM (men having sex with men). In this study a comparison between Real Time PCR Versant CT/GC DNA 1.0 (Siemens) and N. gonorrhoeae culture performances has been conducted testing rectal or pharyngeal secretions collected by E-swabs (Copan).
Methods: Study group. A prospective study was performed with 172 subjects (133 males and 39 females) attending the STD Outpatients Clinic of St. Orsola Hospital, Bologna. All the patients were enrolled because
having unsafe receptive anal and/or pharyngeal sex intercourses. NAAT methods. All the specimens were tested by commercial test Versant CT/GC DNA 1.0 (Siemens). As a confirmation, all the specimens scored positive for N. gonorrhoeae were retested, using the same extraction, by a "home-made" PCR assay, targeting cppB gene. N. gonorrhoeae culture. N. gonorrhoeae was isolated in Thayer-Martin medium and identified by API NH assay (bioMérieux). Antimicrobial susceptibility was assessed by Kirby-Bauer Test. Results: Fifty-three patients provided both the rectal and pharyngeal specimens, 96 patients provided only pharyngeal swabs, whereas only rectal specimens were collected from the remaining 23 patients, for a total of 225 specimens. Versant CT/GC DNA 1.0 gave positive results for N. gonorrhoeae in 13 pharyngeal in 4 rectal samples. Interestingly, all the 4 patients having rectal infection by N. gonorrhoeae had also pharyngeal infection. All the Versant CT/GC DNA 1.0 results were confirmed by cppB "home-made" PCR. Prevalence of rectal infection was 5.3% (4 positive out of 76 patients), whereas prevalence of pharyngeal infection was 8.7% (13/149). No woman was found positive. Culture was far less sensitive than NAAT: only 1 pharyngeal sample and 2 rectal specimens were identified. All of them were resistant to quinolones, but they were susceptible to cephalosporins (cefixime and ceftriaxone).
Conclusions: Rectal and pharyngeal screening should be an essential part of consultations in STD clinics. N. gonorrhoeae culture demonstrated to be far less sensitive than NAAT. Anyway, the use of one single swab for performing both culture and NAAT could be of some interest for those clinicians who need to provide antimicrobial test-driven therapy
Lymphogranuloma venereum in an Italian MSM: concurrent pharyngeal and rectal infection.
No full textAn Italian HIV-positive man having sex with men (MSM) attended the STIs Outpatients Clinic of Sant'Orsola Hospital in Bologna complaining of anal pain and constipation. According to patient's sexual history and repertoires, NAAT testing for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) was performed. Pharyngeal and anal swabs resulted positive for CT DNA detection and the following molecular genotyping identified a L2 serovar, coming to the final diagnosis of pharyngeal and rectal lymphogranuloma venereum (LGV) infection. After an antibiotic therapy with doxycycline 100 mg twice a day for 3 weeks, the patient completely recovered and the test of cure was negative for LGV infection
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
Evaluation of a comparative Western Blot method for early postnatal diagnosis of congenital syphilis
No full textObjectives.
Diagnosis of congenital syphilis (CS) remains difficult. Part of the problem arises because the standard serologic tests are not useful in newborns because IgG transfer across the placenta.
Since Western Blot technique allows the recognition of a specific response towards every single protein, it can be useful to compare IgG immunological profiles of mothers and babies at birth, in order to differentiate between passively transmitted maternal antibodies and antibodies synthesized by the infants.
Methods.
Study group. Thirty infants born to syphilis seropositive mothers were enrolled for this study. At birth, routine serological tests were performed (ARCHITECT® Syphilis TP, Abbott; TPHA and RPR, Randox) on mother/child pairs’ serum specimens.
“Home made WB”. Treponema pallidum antigens, separated by SDS-PAGE, were blotted onto nitrocellulose sheets and incubated overnight with mother/child pairs’ serum specimens.
Criteria for CS diagnosis were the following: presence of specific bands in the newborn’s IgG WB strip different from those found on the corresponding maternal WB strip and/or recognition on IgM WB strip of at least 2 out the 4 following bands Tp47, TmpA, Tp17 and Tp15, including at least one with low molecular weight.
Results.
Out of the 30 infants born to syphilis seropositive mothers, we found 3 babies with different IgG WB profiles from those of their own mothers. Two out these three newborns had also positive IgM WB result. Routine serological testing results of all the 30 newborns showed similar values to those of their own mothers.
Conclusion.
The use of comparative IgG WB test enabled us to diagnose CS in three cases in which the infection would have not been detected by classical serology techniques. Therefore the routine use of comparative IgG WB assay at birth on newborn-mother pairs could be a welcome addition to the conventional laboratory methods used for the diagnosis of CS
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
VALUTAZIONE DEL SISTEMA IMMULITE® 2000 PER LO SCREENING SIEROLOGICO DELLE INFEZIONI DA TOXOPLASMA GONDII, CYTOMEGALOVIRUS E ROSOLIA
No full textIntroduzione
Lo screening sierologico per il complesso TORCH riveste un ruolo fondamentale nella prevenzione delle infezioni a trasmissione materno-fetale. L’elevato numero di analisi quotidiane impone ai laboratori l’adozione di nuove metodiche, caratterizzate da tempi rapidi di esecuzione e alto tasso di automazione.
Nel presente studio vengono messi a confronto i dati relativi allo screening sierologico per Toxoplasma gondii (TG), Cytomegalovirus (CMV) e virus della Rosolia ottenuti con IMMULITE® 2000 (Siemens), un analizzatore “random access” basato sulla metodica di chemiluminescenza (CMIA), con quelli ottenuti mediante le tradizionali metodiche immunoenzimatiche (EIA) in micropiastra.
Metodi
Sono stati analizzati 536 sieri pervenuti al laboratorio dell’U.O. di Microbiologia per lo screening sierologico di infezioni da CMV, TG e Rosolia. I sieri sono stati analizzati per la ricerca di IgM e IgG sul sistema BEP III mediante metodica EIA con micropiastre Enzygnost (Siemens) e su IMMULITE® 2000. Come metodi di conferma, sono stati utilizzati i test ELFA Vidas (bioMerieux).
Risultati
La concordanza dei test IgG IMMULITE® con le rispettive analisi in micropiastra è stata, rispettivamente, del 98.7% per TG, 98.2% per CMV e 99.8% per Rosolia. Infine, per i test IgM la concordanza tra i due sistemi è stata del 97.9% per TG, 99% per CMV e 97.2% per Rosolia.
Conclusioni
Il sistema IMMULITE® 2000 permette di effettuare fino a 200 test/ora, garantendo al laboratorio un notevole risparmio di tempo rispetto alle analisi in micropiastra. I valori di concordanza ottenuti, unitamente all’alto livello di automazione e alla elevata produttività rendono il sistema IMMULITE® 2000 una buona alternativa per lo screening anticorpale del complesso TORCH. Per quanto riguarda la ricerca di anticorpi di classe IgM, si consiglia di affiancare a tale sistema un adeguato metodo di conferma, per completezza di rispost
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
VALUTAZIONE DELLE PERFORMANCE ANALITICHE DI IMMULITE® 2000 E BIOPLEX® 2200 PER LO SCREENING SIEROLOGICO DELLE INFEZIONI DA TOXOPLASMA GONDII, CYTOMEGALOVIRUS E VIRUS DELLA ROSOLIA
No full textIntroduzione
La tendenza all’accorpamento dei laboratori e il conseguente aumento del numero di richieste giornaliere pone sempre più la necessità di adottare sistemi ad elevata automazione. Negli ultimi anni, nell’ambito dello screening in gravidanza per le infezioni del complesso TORCH, sono stati proposti diversi sistemi automatizzati “random access”. In questo studio sono stati confrontati i dati relativi allo screening sierologico per Toxoplasma gondii (TG), Cytomegalovirus (CMV) e virus della Rosolia ottenuti con due diversi analizzatori: IMMULITE® 2000 (Siemens) e BioPlex® 2200 (Bio-Rad).
Metodi
Sono stati studiati 288 sieri pervenuti al Laboratorio dell’U. O. Microbiologia con richiesta contemporanea di screening IgG e IgM per TG, CMV e virus della Rosolia. Tutti i sieri sono stati analizzati con BioPlex® 2200 e IMMULITE® 2000. I test per il sistema BioPlex® 2200 sfruttano la tecnologia del “Multiplex Flow Immunoassay”, in grado di rilevare contemporanemente la presenza di anticorpi nei confronti di diversi analiti, mentre i kit per IMMULITE® 2000 sono basati sul principio della chemiluminescenza amplificata. Nel caso di risultati discordanti per il dosaggio delle IgM sono stati utilizzati come conferma i test ELFA Vidas (bioMerieux).
Risultati
La concordanza per IgG tra i due sistemi è stata, rispettivamente, del 98.2% per TG, 95.8% per CMV e 98.6% per Rosolia. Per IgM la concordanza è stata, rispettivamente, pari a 92.7% per TG, 95.8% per CMV e 96.5% per Rosolia. Tutti i sieri con risultati discordanti per IgM sono risultati negativi quando analizzati con i test ELFA.
Conclusioni
Entrambi i sistemi “random access” hanno dimostrato valide performance analitiche e, grazie all’alta capacità produttiva e alla completa automazione, sia BioPlex® 2200, sia IMMULITE® 2000 risultano adatti nella gestione della routine di laboratorio per lo screening del complesso TORCH. In caso di riscontro di anticorpi di classe IgM, è consigliabile affiancare un adeguato metodo di conferma
Diagnosis of pharyngeal and rectal Neisseria gonorrhoeae infections
No full textObjectives.
Despite nucleic acid amplification tests (NAAT) are widely used to detect Neisseria gonorrhoeae infections, so far no commercial kit has been cleared for testing rectal or pharyngeal swab samples, even if anal and/or oral sex practices are common.
In this study, a comparison between Real Time PCR Versant CT/GC DNA 1.0 (Siemens) and N. gonorrhoeae culture performances has been conducted, testing rectal or pharyngeal secretions collected by E-swabs (Copan).
Methods.
Study group. A prospective study was performed with 171 subjects (130 males and 41 females) attending the STD Outpatients Clinic of St. Orsola Hospital, Bologna. All the patients were enrolled because having unsafe receptive anal and/or pharyngeal sex intercourses.
NAAT methods. All the specimens were tested by Versant CT/GC DNA 1.0. As a confirmation, all the specimens scored positive for N. gonorrhoeae were retested, using the same extraction, by a “home-made” PCR assay, targeting cppB gene.
N. gonorrhoeae culture. Bacteria were isolated in Thayer-Martin medium and identified by API NH assay (bioMérieux). Antimicrobial susceptibility was assessed by Kirby-Bauer Test.
Results.
A total of 227 samples were obtained. In particular, 56 patients provided both the specimens, 89 patients provided only pharyngeal swabs, whereas only rectal specimens were collected from the remaining 26 patients.
Versant CT/GC DNA 1.0 gave positive results for N. gonorrhoeae in 13 pharyngeal in 7 rectal samples, all from MSM. All the Versant reactive results were confirmed by “home-made” PCR. Prevalence of rectal infection was 8.5% (7 positive out of 82 patients), whereas prevalence of pharyngeal infection was 9.0% (13/145). Culture was far less sensitive than NAAT, since only 4 samples were identified. All of them were resistant to quinolones, but susceptible to cephalosporins (cefixime and ceftriaxone).
Conclusions.
Pharyngeal and/or rectal screening for gonorrhoea should be considered essential in consultations for MSM in STD settings
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