1,720,969 research outputs found
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
Retrospective analysis on the efficacy of corticosteroid prophylaxis prior to elective caesarean section to reduce neonatal respiratory complications at term of pregnancy: Review of literature
No full textPurpose: Our purpose was to conduct a systematic review of the literature to determine whether synthetic pharmaceutical glucocorticoids (betamethasone and dexamethasone) are safe as well as effective in reducing neonatal respiratory morbidity at term of pregnancy prior to elective caesarean section. The overall incidence of respiratory disorders is estimated at 2.8 %, and the main risk factors are gestational age and mode of delivery. Newborns delivered by elective caesarean section (CS after 37 weeks) are more susceptible to serious respiratory complications than babies born by vaginal delivery. Neonatal respiratory morbidity at term of pregnancy is low but not negligible. Further, it is increasing due to a drastic decline in trial of labour in those pregnant women who underwent a caesarean section in the past. Because prophylaxis is inexpensive, easy to administer, and safe, other studies should be conducted to confirm its effectiveness. Methods: We conducted a systematic review of literature since 1965 on the discovery of action mechanisms, pharmaceutical development, proper dosage, and potential side effects of corticosteroids on the mother and offspring to extrapolate their efficacy as no clinical trial has directly demonstrated it. Results: We extrapolated no negative effects on mother and foetus behaviour. Conclusions: Human studies suggest that corticosteroid administration may become a proper clinical indication prior to caesarean section in the reduction of neonatal respiratory problems. © 2013 Springer-Verlag Berlin Heidelberg
Pronuclear morphology evaluation for fresh in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles: A systematic review
Full text linkThe current systematic review was aimed to assess the effectiveness of the zygote morphology evaluation in fresh in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles. All available studies reporting on zygote morphology and clinical and/or biological outcomes were analyzed. Forty studies were included in the final analysis. Fourteen different zygote scoring systems were employed. Zygote morphology correlated significantly with embryo quality and cleavage, blastocyst stage, embryonic chromosome status, in a high proportion of the studies which assessed the specific outcome [15/25 (60%), 15/20 (75%), 7/8 (87.5%), 6/6 (100%), respectively]. On the other hand, only a reduced proportion of papers showed a statistically significant relationship between implantation, pregnancy and delivery/live-birth rates and zygote morphology score [12/23 (52.2%), 12/25 (48%), 1/4 (25%), respectively]. In conclusion, our findings demonstrate the lack of conclusive data on the clinical efficacy of the zygote morphology evaluation in fresh IVF/ICSI cycles, even if biological results showing a good relationship with embryo viability suggest a role in cycles in which the transfer/freezing is performed at day 1. © 2013Nicoli et al.; licensee BioMed Central Ltd
The effect of the 2004 Italian legislation on perinatal outcomes following assisted reproduction technology
No full textObjective: To assess the perinatal outcomes of the first three years under the 2004 Italian reproductive legislation obligating transfer of all embryos resulting from insemination of ≤3 oocytes. Study design: We compared the perinatal results of clinical assisted reproductive technology (ART) pregnancies during the three years following the new Italian legislation with the previous three years. Results: There were 583 and 571 clinical pregnancies during the respective periods. Before the law, the overall embryonic and fetal loss rates were significantly higher resulting in a significantly lower rate of live born infants and significantly fewer clinical pregnancies with at least one live born infant. Quadruplet and quintuplet pregnancies were entirely eliminated following the 2004 law but the neonatal mortality rate was not different between the two study periods. Conclusion: The 2004 Italian infertility legislation led to improved quantitative and qualitative outcomes of ART. © 2009 by Walter de Gruyter
DETECTION OF ANTIGEN-SPECIFIC ANTIBODIES IN SERUM AND FOLLICULAR FLUIDS BY PROTEIN MICROARRAYS.
No full textBackground. Wide spectrum serological screening of women prior to or during pregnancy may greatly help in preventing vertically transmitted infections (VTI) and their severe consequences to the foetus/newborn. Protein microarrays, made up by spotting many antigens onto a restricted area of a microscope slide, allow to detect, in one shot, specific antibodies against a wide range of antigenic specificities.
Objectives. To detect, in paired serum and follicular fluid (FF) samples, antigen-specific antibodies against vertically transmitted pathogens by protein microarrays; to investigate the potential relation between antibody profiles and pregnancy outcome.
Methods. Serum and FF paired samples were collected from 102 women undergoing in vitro fertilization (IVF). Antigens, human antibodies and controls were spotted in an orderly manner by high speed robotics. Microarrays were processed with serum or FF and the occurred immunocomplexes were revealed by fluorescently-labelled secondary antibodies. The fluorescent signals were read by a laser scanner and quantified by a dedicated software.
Conclusions. Antigen-specific antibodies can be effectively detected in serum and FF by microarray. The presence or absence of certain antigen-specific antibodies is significantly related to clinical parameters such as the number of inseminated good quality oocytes or the number of successful embryo transfers. These results encourage protein microarrays employment for wide spectrum investigations in diagnosing VTI; in particular, the use of biological matrices other than serum may help addressing yet unravelled questions
Embryo quality before and after slow freezing: Viability, implantation and pregnancy rates in 627 single frozen-thawed embryo replacement cycles following failure of fresh transfer
No full textFrozen embryo transfer cycles are now common practice, however, various aspects regarding the potential of frozen embryos remain unclear. The main goal of the present study was to assess embryo quality before and after slow freezing procedure, and more specifically blastomere loss and embryo quality as indicator of viability. A single center retrospective analysis of single frozen-thawed embryo replacements (s-FER) was performed. The embryo quality before and after slow freezing and thawing, implantation, and pregnancy rates were recorded. One hundred and twenty seven s-FER were included in the final analysis. The probability of achieving an ongoing pregnancy was significantly associated with embryo quality and the percentage of blastomere loss after thawing. Considering thawed embryos, a non-significant difference in term of implantation rate was observed, regardless to their post-thawing quality and the percentage of blastomeres loss. In conclusion, current data suggest that thawed embryos are capable of implantation regardless of their morphological quality and the degree of cryoinjury sustained
VALUTAZIONE DEI PROFILI IgG E IgM NEI CONFRONTI DI PATOGENI A TRASMISSIONE VERTICALE IN DIVERSE MATRICI BIOLOGICHE MEDIANTE MICROARRAY PROTEICO
No full textLo screening sierologico su larga scala, effettuato prima o durante la gravidanza, fornisce un mezzo efficace per prevenire infezioni a trasmissione verticale (ITV) e le loro gravi conseguenze per il prodotto del concepimento. Utilizzando un microarray proteico da noi messo a punto (1), abbiamo voluto determinare i livelli di anticorpi antigene-specifici nei confronti di patogeni a trasmissione verticale nel siero, nei fluidi follicolari (FF) e nei fluidi amniotici (FA) di pazienti gravide, al fine di correlare profili anticorpali specifici con l’esito della gravidanza.
Siero e FF sono stati prelevati da 102 pazienti sottoposte a trattamenti di procreazione medicalmente assistita. FA sono stati ottenuti da 100 pazienti di cui 50 con parto pretermine e 50 con gravidanza a termine. I microarray, allestiti con antigeni, anticorpi e controlli di segnale, come precedentemente descritto (1) sono stati processati con siero, FF o FA e la formazione degli immunocomplessi è stata rivelata mediante anticorpi secondari marcati in fluorescenza. I segnali sono stati letti con uno scanner contenente laser a differente lunghezza d’onda e successivamente quantificati ed analizzati da un software dedicato. Il saggio ha consentito di rivelare in maniera efficace anticorpi antigene-specifici in tutte le matrici saggiate. In particolare, la presenza o assenza di determinati anticorpi nelle coppie di campioni siero/FF provenienti dalla stessa paziente è risultata significativamente correlata a determinati parametri clinici, quali il numero di oociti inseminati di buona qualità o il numero di trasferimenti embrionali avvenuti con successo. L’analisi dei profili anticorpali sui FA del secondo gruppo di 100 pazienti è tuttora in corso.
I dati ottenuti incoraggiano l’utilizzo del microarray proteico per indagini ad ampio spettro nella diagnosi di ITV; inoltre, l’utilizzo di matrici biologiche differenti dal siero può fornire un valido contributo per la risoluzione di problemi ancora aperti.
(1) Ardizzoni et al., Eur J Clin Microbiol Infect Dis, 2009
I MICROARRAY PROTEICI: NUOVI STRUMENTI DI INDAGINE NELLA DIAGNOSTICA DELLE INFEZIONI DA PATOGENI DEL COMPLESSO TORCH.
No full textLo screening sierologico su larga scala, effettuato prima o durante la gravidanza, fornisce un mezzo efficace per prevenire le infezioni a trasmissione verticale (ITV) e le loro gravi conseguenze per il prodotto del concepimento. Utilizzando un microarray proteico da noi messo a punto (1), abbiamo voluto determinare i livelli di anticorpi antigene-specifici nei confronti di patogeni a trasmissione verticale nel siero, nei liquidi follicolari (LF) e nei liquidi amniotici (LA) di pazienti gravide sottoposte a IVF, al fine di correlare profili anticorpali specifici con l’esito della gravidanza.
Sieri e LF sono stati prelevati da 102 pazienti sottoposte a trattamenti di procreazione medicalmente assistita. LA sono stati ottenuti da 100 pazienti di cui 50 con parto pretermine e 50 con parto a termine. I microarray, allestiti con antigeni, anticorpi e controlli di segnale, come precedentemente descritto (1), sono stati processati con siero, LF o LA e la formazione degli immunocomplessi è stata rivelata mediante anticorpi secondari marcati in fluorescenza. I segnali sono stati letti con uno scanner contenente laser a differenti lunghezze d’onda e successivamente quantificati ed analizzati da un software dedicato. Il saggio ha consentito di rivelare in maniera efficace IgG antigene-specifiche in tutte le matrici saggiate, mentre anticorpi IgM sono stati rilevati solamente nel siero. In particolare, la presenza o assenza di determinati anticorpi IgG nelle coppie di campioni siero/LF provenienti dalla stessa paziente è risultata significativamente correlata a parametri clinici, quali il numero di oociti inseminati di buona qualità o il numero di trasferimenti embrionali avvenuti con successo (2). L’analisi dei profili anticorpali sui LA nel secondo gruppo di 100 pazienti è tuttora in corso. Su questo gruppo di pazienti, inoltre, si sta impiegando un microarray commerciale per valutare la presenza di citochine e/o chemochine da correlare eventualmente con il quadro clinico della paziente e con l’esito della gravidanza (parto a termine o pretermine). Risultati preliminari hanno consentito di dimostrare l’efficacia dell’approccio, evidenziando la presenza di livelli significativi di alcune citochine nei fluidi amniotici. Sono in corso indagini per determinare il contenuto di citochine in tutti i LA oggetto di studio.
I dati finora ottenuti sostengono fortemente l’utilizzo del microarray proteico in indagini ad ampio spettro nella diagnosi di ITV; inoltre, l’utilizzo di matrici biologiche differenti dal siero può fornire un valido contributo per la risoluzione di quesiti diagnostici ancora irrisolti.
(1) Ardizzoni et al., Eur J Clin Microbiol Infect Dis, 2009.
(2) Ardizzoni et al., J Reprod Immunol, 2011
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
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