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Purpose: Remote ischemic conditioning (RIC) is a maneuver involving brief cycles of ischemia reperfusion in an individual’s limb. In the early stage of experimental NEC, RIC decreased intestinal injury and prolonged survival by counteracting the derangements in intestinal microcirculation. A single-center phase I study demonstrated that the performance of RIC was safe in neonates with NEC. The aim of this phase II RCT was to evaluate the safety and feasibility of RIC, to identify challenges in recruitment, retainment, and to inform a phase III RCT to evaluate efficacy. Methods: RIC will be performed by trained research personnel and will consist of four cycles of limb ischemia (4-min via cuff inflation) followed by reperfusion (4-min via cuff deflation), repeated on two consecutive days post randomization. The primary endpoint of this RCT is feasibility and acceptability of recruiting and randomizing neonates within 24 h from NEC diagnosis as well as masking and completing the RIC intervention. Results: We created a novel international consortium for this trial and created a consensus on the diagnostic criteria for NEC and protocol for the trial. The phase II multicenter-masked feasibility RCT will be conducted at 12 centers in Canada, USA, Sweden, The Netherlands, UK, and Spain. The inclusion criteria are: gestational age < 33 weeks, weight ≥ 750 g, NEC receiving medical treatment, and diagnosis established within previous 24 h. Neonates will be randomized to RIC (intervention) or no-RIC (control) and will continue to receive standard management of NEC. We expect to recruit and randomize 40% of eligible patients in the collaborating centers (78 patients; 39/arm) in 30 months. Bayesian methods will be used to combine uninformative prior distributions with the corresponding observed proportions from this trial to determine posterior distributions for parameters of feasibility. Conclusions: The newly established NEC consortium has generated novel data on NEC diagnosis and defined the feasibility parameters for the introduction of a novel treatment in NEC. This phase II RCT will inform a future phase III RCT to evaluate the efficacy and safety of RIC in early-stage NEC.

Purpose:To retrospectively assess the efficacy of Nd:YAG laser vitreolysis for managing symptomatic vitreous floaters using vitreous opacity area quantification. Methods: Patients who underwent laser vitreolysis from May 2015 to February 2020 at a private clinic with a minimum follow-up of 3-months were enrolled into this retrospective, non-comparative cohort study. Vitreous opacity areas quantification was the primary outcome measure. Secondary outcome measures included patient satisfaction outcomes post-vitreolysis, the need to proceed to vitrectomy, best corrected visual acuity (BCVA) and intraocular pressure (IOP), recorded at baseline and all follow-ups. Results:100 eyes from 100 patients were followed for an average of 15 months (range: 3-53 months). Of these, complete resolution (35%) or improvement (54%) of vitreous opacities was observed with vitreous opacity area quantification, constituting a treatment success of 89%. 78% reported complete resolution or improvement in floater symptoms at the 1-month post-vitreolysis visit. At the last follow-up, a similar report was noted in 72% of eyes. There was less need for vitrectomy in 86 eyes. There was significant improvement in BCVA, as well as a reduction in IOP, from baseline at the final post-operative visits (pConclusion: The findings of this study suggest that Nd:YAG laser vitreolysis may result in objective and symptomatic improvements in patients undergoing the procedure, with a limited rate of complications. Floater symptoms may recur with time following laser vitreolysis, necessitating the need for repetition. More clinical studies are needed to validate these findings.

Résumé La paralysie néonatale du plexus brachial, qui se manifeste à la naissance, peut être débilitante et avoir des conséquences prolongées. La présentation à la naissance dépend de l’importance de la lésion nerveuse et peut varier entre une faiblesse transitoire et une parésie globale qui touche l’amplitude active des mouvements. Il est essentiel de procéder à des examens cliniques sériels après la naissance et pendant la période néonatale (jusqu’à l’âge d’un mois) pour évaluer le rétablissement et prédire le pronostic à long terme. Le présent document de principes décrit l’évaluation des facteurs de risque des nouveau-nés à la naissance, l’orientation précoce vers une équipe multidisciplinaire spécialisée et les communications entre les intervenants communautaires et les spécialistes pour optimiser le pronostic pendant l’enfance.

Finite element (FE) technique has been used extensively to have a deeper understanding on the mechanics of metal cutting and for process optimization. The accuracy of the model is dependent on both the highly non-linear material plasticity model and the simulated friction condition between contacting surfaces. Hence, majority of the predicted results were validated from direct or indirect experimental results. Measurement of cutting forces magnitude and temperature field are direct techniques to validate the model. Indirect methods are chip morphology and residual stresses measurement from the newly generated surface. In this paper, a unique indirect method is proposed to validate the accuracy of the FE model. This method predicts the tool wear rate by using the average contact pressure and interface temperature acquired from finite element simulation, as the inputs for the Usui’s tool wear rate equation. Orthogonal cutting experiments were performed in specific ranges of cutting speed and feed rate. The workpiece material used was AISI 1045 at 86 HRB, and tool material was uncoated carbide. Tool cutting edge geometry was analyzed in different steps of the cutting process, and worn edge geometries were obtained. The worn edge geometries were then used to build the FE cutting models. Based on the simulation results when the flank wear length increases, the temperature field prediction showed that the region of maximum temperature shifted from the rake face to the flank face region. The contact pressure increased substantially with cutting speed rather than feed rate. The predicted wear rate agreed well with experimental results. Using tool wear rate to predict the accuracy of the FE cutting model is limited to the orientation of the rake and flank face surfaces.

BACKGROUND The impact of suboptimal intakes on neurodevelopment of very low-birth-weight (VLBW

Objectives To evaluate the utility of ultrasound markers in the management of pregnancies complicated by preterm prelabor rupture of membranes (PPROM) between 23 + 0 and 33 + 6 weeks' gestation, and to assess the ability of ultrasound markers to predict adverse neonatal outcomes. Methods This was a retrospective cohort study of all patients with PPROM between 23 + 0 and 33 + 6 weeks' gestation and latency period (PPROM to delivery) > 48 h, who delivered before 34 weeks' gestation at a tertiary referral center between 2005 and 2017. All patients underwent a non-stress test daily and an ultrasound scan twice a week for assessment of amniotic fluid volume, biophysical profile (BPP) and umbilical artery (UA) pulsatility index (PI). In patients with suspected fetal growth restriction, fetal middle cerebral artery (MCA)-PI was also assessed and the cerebroplacental ratio (CPR) calculated. The last ultrasound examination performed prior to delivery was analyzed. We compared the characteristics and outcomes between women who were delivered owing to clinical suspicion of chorioamnionitis and those who were not delivered for this indication. The primary objective was to evaluate the utility of ultrasound in the management of patients with PPROM. The secondary objective was to assess the diagnostic performance of ultrasound markers (BPP score 95th percentile, MCA-PI Results A total of 504 women were included in the study, comprising 120 with suspected chorioamnionitis and 384 without. Women with suspected chorioamnionitis, compared with those without, were less likely to be nulliparous (34.2% vs 45.3%; P = 0.03) and more likely to have fever (50.8% vs 2.6%; P 95th percentile was similar between the two groups. There was a higher incidence of composite adverse neonatal outcome in the group with suspected chorioamnionitis than in the group without (78.3% vs 64.3%, respectively; P = 0.004). However, on logistic regression analysis, none of the ultrasound markers evaluated was found to be associated with chorioamnionitis or composite adverse neonatal outcome, and they all had a poor diagnostic performance for the prediction of chorioamnionitis and composite adverse neonatal outcome. Conclusions Commonly used ultrasound markers in pregnancies complicated by PPROM were similar between women delivered for suspected chorioamnionitis and those delivered for other indications, and performed poorly in predicting composite adverse neonatal outcome. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.