Situating the KTA gap in clinical research: Foregrounding a discontinuity in practices.

In this study, I will claim that we need to rearticulate the so-called "knowledge-to-action" (KTA) gap metaphor in clinical research as a discontinuity of practices. In clinical research, there is a significant delay between the production of research results and their application in policy and practice. These difficulties are normally conceptualized through the metaphor of the KTA gap between scientific knowledge and practical applications. I will advise that it is important to reformulate the terms of the problem, as they suggest the difficulty lies only in the results generated on one side (the laboratory), not reaching the other side (the clinic), and that crossing the gap requires us to simply optimize the transfer and exchange of knowledge. This perspective considers knowledge separate from the practices from which it was generated, making it into a thing that can be transported and transferred largely independently from the communities that produce or "possess" it. The paper then revises the terms of the problem, shifting the focus from knowledge understood as independent from practical circumstances to the situated practices of knowing. Knowledge will then be understood as enacted in practice, emerging as people interact recurrently in the context of established practices. When people coming from different domains and with different "ends-in-view" must coordinate, they have to deal with conceptual and practical tensions, different ways of doing things with their surroundings, and different normative practices. Considering that, the KTA gap will be revised, not as a gap between scientific results and their application in clinical practice, but as a discontinuity in how communities engage with their local contexts and what they perceive as relevant for their activities.

Sex-specific influence of the vacuolar adenosine triphosphatase a2 isoform on outcome in twin pregnancies.

PROBLEM: The influence of fetal sex on immune responses in multifetal pregnancies remains incompletely elucidated. The a2 isoform of vacuolar adenosine triphosphatase (a2V) is expressed on the cell membrane of maternal lymphoid cells and contributes to down-regulation of pro-inflammatory immune responses during gestation. The association between fetal sex and a2V expression on peripheral blood mononuclear cells (PBMCs) from mothers with twin gestations was assessed. METHOD OF STUDY: Patients in this prospective study were 93 women with twin pregnancies in their mid-second or early third trimester-27 with two male, 30 with two female and 36 with one male and one female fetus. PBMCs were isolated and a2V was measured by ELISA in cell lysates. Demographic and clinical data were subsequently obtained and correlations between a2V and fetal sex, birthweight and pregnancy outcome were assessed by the Mann-Whitney and Spearman rank correlation tests. RESULTS: The mean a2V level was highest when both fetuses were male (2.0 ng/mL) and lowest when both were female (1.5 ng/mL; P = 0.0184). Only when both fetuses were female did the a2V concentration negatively correlate with birthweight of the 1st (P = 0.0011) and 2nd (P = 0.0044) born fetus and with gestational age at delivery (P = 0.0018). There were no associations between a2V and these outcomes in male only or mixed twin pregnancies. CONCLUSION: We conclude that the a2V-mediated regulation of maternal immunity during twin pregnancies is influenced by fetal sex.

Twin pregnancies after assisted reproductive technologies: the role of maternal age on pregnancy outcome.

OBJECTIVES: Our aim was to investigate whether advanced maternal age (≥40years) still impairs the outcome of twin pregnancies after assisted reproductive techniques (ART). STUDY DESIGN: The retrospective observational study evaluated 430 nulliparous dichorionic diamniotic twin pregnancies conceived with ART. The population was divided into women <40 years old (Group A, n=265) and ≥40 years old (Group B, n=165). RESULTS: Gestational diabetes mellitus and gestational hypertension/preeclampsia were significantly more frequent in nulliparous twin pregnancies after ART ≥40years compared to <40years (p=0.021 and p<0.001, respectively). In univariate analysis of twin pregnancies after ART, there was only a trend of higher incidence of total preterm birth (PB) rate within mother aged ≥40 years old (p=0.104). However, Group A showed higher rate of spontaneous preterm birth (SPB) <37 weeks, whereas Group B showed significantly higher rate of iatrogenic PB <37 weeks of gestation (p=0.023 and p=0.001, respectively). For delivery <32 weeks of gestation, the rate of SPB in Group A was significantly higher (p=0.002). A higher incidence of PB was observed in Group B after heterologous treatment (p<0.001). Despite this, the absolute prevalence of PB in the entire population is higher in Group A, both after autologous (22.5%) and heterologous (25%) ART treatment, than in Group B (10.1% vs 21.4%). CONCLUSIONS: Our data indicate that nulliparous twin pregnancies conceived with ART in mothers ≥40 years old did not show significantly higher incidence of PB, even if an increased rate of iatrogenic PB <37 weeks is showed.