Intrapartum PCR assay is a fast and efficient screening method for Group B Streptococcus detection in pregnancy.

OBJECTIVES: The aim of the study is to verify the usefulness of a real-time polymerase chain reaction versus the culture for ante- and intrapartum group B Streptococcus maternal colonization (GBS) and prevalence of discordance during the period between an antepartum screening and delivery. MATERIAL AND METHODS: The study involved 106 pregnant women aged 18 to 39 years. Rectovaginal samples were collected according to CDC guidelines at 35-37 weeks of gestation as well as in the first stage of labour, during physical examination and were analyzed using two independent diagnostic methods: microbiological culture with standard culture and polymerase chain reaction with real-time assay. RESULTS: The discordance between antenatal and intrapartum GBS prevalence has been demonstrated as well as differences associated with diagnostic strategies, culture and PCR. CONCLUSIONS: Intrapartum detection of GBS colonization using culture or Real-Time PCR assay as well, regardless of antenatal screening test for GBS, is very useful in identifying women who require implementation or withdrawal from prophylactic intrapartum antibiotic therapy. Real-Time PCR is a quick efficient method for GBS screening in pregnant women, which can be even applied during labor due to its short time of analyzing and high sensitivity and specificity. The above fact may indicate the need to perform the GBS test in the intrapartum period in all pregnant GBS negative women using PCR assay as a more adequate diagnostic method as the procedure could reduce the risk of a neonatal GBS infection subsequently to a prophylactic antibiotic therapy in women with an intrapartum positive GBS.

A Perception-driven Hybrid Decomposition for Multi-layer Accommodative Displays.

Multi-focal plane and multi-layered light-field displays are promising solutions for addressing all visual cues observed in the real world. Unfortunately, these devices usually require expensive optimizations to compute a suitable decomposition of the input light field or focal stack to drive individual display layers. Although these methods provide near-correct image reconstruction, a significant computational cost prevents real-time applications. A simple alternative is a linear blending strategy which decomposes a single 2D image using depth information. This method provides real-time performance, but it generates inaccurate results at occlusion boundaries and on glossy surfaces. This paper proposes a perception-based hybrid decomposition technique which combines the advantages of the above strategies and achieves both real-time performance and high-fidelity results. The fundamental idea is to apply expensive optimizations only in regions where it is perceptually superior, e.g., depth discontinuities at the fovea, and fall back to less costly linear blending otherwise. We present a complete, perception-informed analysis and model that locally determine which of the two strategies should be applied. The prediction is later utilized by our new synthesis method which performs the image decomposition. The results are analyzed and validated in user experiments on a custom multi-plane display.