Aim: The aim was to compare resuscitators' estimates of tidal volume (V_T) and face mask leak with measured values during positive pressure ventilation (PPV) of newborn infants in the delivery room. Patients and methods: The authors measured inflating pressures and V_T delivered using a respiratory function monitor, and calculated face mask leak. After 60 s of PPV, resuscitators were asked to estimate V_T and face mask leak. These estimates were compared with measurements taken during the previous 30 s. Results: The authors studied 20 infants who received a mean (SD) of 21 (6) inflations during the 30 s. The median (IQR) expired tidal volume (V_Te) delivered was 8.7 ml/kg (5.3–11.3). V_Te varied widely during each resuscitation and between resuscitators. Five resuscitators could not estimate V_Te, one overestimated and 14 underestimated their median delivered V_Te. The median (IQR) face mask leak was 29% (16–63%). Leak also varied widely during each resuscitation and between resuscitators. One resuscitator could not estimate mask leak, four overestimated leak and 15 underestimated leak. Conclusion: During face mask ventilation in the delivery room, V_T and face mask leak were large and variable. The resuscitators were unable to accurately assess their face mask leak or delivered V_T.

Objective: Use of video recordings of newborn infants to determine: (1) if clinicians agreed whether infants were pink; and (2) the pulse oximeter oxygen saturation (Spo ₂) at which infants first looked pink. Methods: Selected clips from video recordings of infants taken immediately after delivery were shown to medical and nursing staff. The infants received varying degrees of resuscitation (including none) and were monitored with pulse oximetry. The oximeter readings were obscured to observers but known to the investigators. A timer was visible and the sound was inaudible. The observers were asked to indicate whether each infant was pink at the beginning, became pink during the clip, or was never pink. If adjudged to turn pink during the clip, observers recorded the time this occurred and the corresponding Spo ₂ was determined. Results: 27 clinicians assessed videos of 20 infants (mean (SD) gestation 31(4) weeks). One infant (5%) was perceived to be pink by all observers. The number of clinicians who thought each of the remaining 19 infants were never pink varied from 1 (4%) to 22 (81%). Observers determined the 10 infants with a maximum Spo ₂ ⩾95% never pink on 17% (46/270) of occasions. The Spo ₂ at which individual infants were perceived to turn pink varied from 10% to 100%. Conclusion: Among clinicians observing the same videos there was disagreement about whether newborn infants looked pink with wide variation in the Spo ₂ when they were considered to become pink.

Introduction Preterm infants with inadequate breathing receive positive pressure ventilation (PPV) by mask with variable success. The authors examined recordings of PPV given to preterm infants in the delivery room for prevalence of mask leak and airway obstruction. Methods and patients The authors reviewed recordings of infants at 75%. Results The authors analysed recordings of 56 preterm infants. Obstruction occurred in 14 (26%) recordings and leaks in 27 (51%). Both obstruction and mask leaks were seen in eight (14%) recordings, and neither was seen in 15 (27%). Obstruction occurred at a median (IQR) of 48 (24–60) s after the start of PPV. A median (range) of 22 (3–83) consecutive obstructed inflations were delivered. Face-mask leaks occurred from the first inflation in 19/27 (70%) and in the remaining eight at a median (IQR) of 30 (24–46) s after the start of PPV. A median (range) of 10 (3–117) consecutive inflations with a leak >75% were delivered. Conclusion Airway obstruction and face-mask leak are common during the first 2 min of PPV. An RFM enables detection of important airway obstruction and mask leak.

This study investigates ultrasound assisted extraction (UAE) process parameters (time, frequency and solvent) to obtain high yields of phlorotannins, flavonoids, total phenolics and associated antioxidant activities from 11 brown seaweed species. Optimised UAE conditions (35 kHz, 30 min and 50% ethanol) significantly improved the extraction yield from 1.5-fold to 2.2-fold in all seaweeds investigated compared to solvent extraction. Using ultrasound, the highest recovery of total phenolics (TPC: 572.3 ± 3.2 mg gallic acid equivalent/g), total phlorotannins (TPhC: 476.3 ± 2.2 mg phloroglucinol equivalent/g) and total flavonoids (TFC: 281.0 ± 1.7 mg quercetin equivalent/g) was obtained from Fucus vesiculosus seaweed. While the lowest recovery of TPC (72.6 ± 2.9 mg GAE/g), TPhC (50.3 ± 2.0 mg PGE/g) and TFC (15.2 ± 3.3 mg QE/g) was obtained from Laminaria digitata seaweed. However, extracts from Fucus serratus obtained by UAE exhibited the strongest 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity (29.1 ± 0.25 mg trolox equivalent/g) and ferric reducing antioxidant power (FRAP) value (63.9 ± 0.74 mg trolox equivalent/g). UAE under optimised conditions was an effective, low-cost and eco-friendly technique to recover biologically active polyphenols from 11 brown seaweed species.

Transcriptional profiling is a key technique in the study of cell biology that is limited by the availability of reagents to uniquely identify specific cell types and isolate high quality RNA from them. We report a Method for Analyzing RNA following Intracellular Sorting (MARIS) that generates high quality RNA for transcriptome profiling following cellular fixation, intracellular immunofluorescent staining and FACS. MARIS can therefore be used to isolate high quality RNA from many otherwise inaccessible cell types simply based on immunofluorescent tagging of unique intracellular proteins. As proof of principle, we isolate RNA from sorted human embryonic stem cell-derived insulin-expressing cells as well as adult human β cells. MARIS is a basic molecular biology technique that could be used across several biological disciplines.