Influence of zonular tension on molecular transport in the porcine ocular lens.

Introduction: Accommodation is the process of changing the ocular lens' refractive power and focal distance. This process involves application of biomechanical forces on the lens by the surrounding musculature. Previous studies have demonstrated that the lens epithelium demonstrates mechanotransduction and that tension influences its chemical activity.

Two-Year Outcomes of Umbilical Cord Milking in Nonvigorous Infants: A Secondary Analysis of the MINVI Randomized Clinical Trial.

Importance: Compared with early cord clamping (ECC), umbilical cord milking (UCM) reduces delivery room cardiorespiratory support, hypoxic-ischemic encephalopathy, and therapeutic hypothermia in nonvigorous near-term and full-term infants. However, UCM postdischarge outcomes are not known.

Objective: To determine the 2-year outcomes of children randomized to UCM or ECC at birth in the Milking in Nonvigorous Infants (MINVI) trial.

Automated Compression Testing of the Ocular Lens.

The biomechanical properties of the ocular lens are essential to its function as a variable power optical element. These properties change dramatically with age in the human lens, resulting in a loss of near vision called presbyopia. However, the mechanisms of these changes remain unknown.

Caffeine and Less Invasive Surfactant Administration for Respiratory Distress Syndrome of the Newborn.

BACKGROUND: Management strategies for preterm neonates with respiratory distress syndrome include early initiation of continuous positive airway pressure (CPAP) and titration of fractional inspired oxygen and may include the use of less invasive surfactant administration (LISA) to avoid the need for endotracheal intubation. This randomized trial investigated whether early administration of caffeine and LISA would decrease the need for endotracheal intubation in the first 72 hours of life (HoL) compared with caffeine and CPAP alone. METHODS: Eligible neonates born at 24 weeks 0 days to 29 weeks 6 days of gestational age were randomly assigned to receive intravenous caffeine in the first 2 HoL followed by surfactant administration via the LISA method (intervention) or caffeine followed by CPAP (control).

A method for generating zonular tension in the murine eye by embedding and compressing the globe in a hydrogel.

The ocular lens is the primary organ within the eye responsible for accommodation. During accommodation, the lens is subject to biomechanical forces. We previously demonstrated that stretching the porcine lens can increase lens epithelial cell proliferation.

Parental perspectives on a trial using waived informed consent at birth.

Objectives: To determine parental perspectives in a trial with waived consent.

Study Design: Anonymous survey of birth parents with term infants who were randomized using a waiver of consent, administered after infant discharge.

Results: 121 (11%) survey responses were collected.

Umbilical Cord Milking Versus Delayed Cord Clamping in Infants 28 to 32 Weeks: A Randomized Trial.

Objectives: To determine whether rate of severe intraventricular hemorrhage (IVH) or death among preterm infants receiving placental transfusion with UCM is noninferior to delayed cord clamping (DCC).

Methods: Noninferiority randomized controlled trial comparing UCM versus DCC in preterm infants born 28 to 32 weeks recruited between June 2017 through September 2022 from 19 university and private medical centers in 4 countries. The primary outcome was Grade III/IV IVH or death evaluated at a 1% noninferiority margin.

A Narrative Review of the Rationale for Conducting Neonatal Emergency Studies with a Waived or Deferred Consent Approach.

Emergency research studies are high-stakes studies that are usually performed on the sickest patients, where many patients or guardians have no opportunity to provide full informed consent prior to participation. Many emergency studies self-select healthier patients who can be informed ahead of time about the study process. Unfortunately, results from such participants may not be informative for the future care of sicker patients.

Cardiac and cerebral hemodynamics with umbilical cord milking compared with early cord clamping: A randomized cluster crossover trial.

Objective: A large, randomized cluster cross-over trial (N = 1730) comparing intact umbilical cord milking (UCM) to early cord clamping (ECC) in non-vigorous near-term/term newborns demonstrated a reduction in cardiorespiratory interventions at birth and less moderate to severe hypoxic ischemic encephalopathy. We evaluated changes in cerebral tissue oxygenation (StO), pulse oximetry (SpO), pulse rate and fraction of inspired oxygen (FiO) during the first 10 min of life in a subset of infants enrolled in the parent trial.

Study Design: Infants enrolled in the Milking in Non-Vigorous Infants trial that had StO monitoring at birth were included in the sub-study conducted at 3 hospitals the US and Canada.

Oxidative stress in the brain and retina after traumatic injury.

The brain and the retina share many physiological similarities, which allows the retina to serve as a model of CNS disease and disorder. In instances of trauma, the eye can even indicate damage to the brain abnormalities observed such as irregularities in pupillary reflexes in suspected traumatic brain injury (TBI) patients. Elevation of reactive oxygen species (ROS) has been observed in neurodegenerative disorders and in both traumatic optic neuropathy (TON) and in TBI.

Umbilical cord milking in nonvigorous infants: a cluster-randomized crossover trial.

Background: Delayed cord clamping and umbilical cord milking provide placental transfusion to vigorous newborns. Delayed cord clamping in nonvigorous newborns may not be provided owing to a perceived need for immediate resuscitation. Umbilical cord milking is an alternative, as it can be performed more quickly than delayed cord clamping and may confer similar benefits.

Arvcf Dependent Adherens Junction Stability is Required to Prevent Age-Related Cortical Cataracts.

The etiology of age-related cortical cataracts is not well understood but is speculated to be related to alterations in cell adhesion and/or the changing mechanical stresses occurring in the lens with time. The role of cell adhesion in maintaining lens transparency with age is difficult to assess because of the developmental and physiological roles that well-characterized adhesion proteins have in the lens. This report demonstrates that Arvcf, a member of the p120-catenin subfamily of catenins that bind to the juxtamembrane domain of cadherins, is an essential fiber cell protein that preserves lens transparency with age in mice.

A Review of Lens Biomechanical Contributions to Presbyopia.

Presbyopia-the progressive loss of near focus with age-is primarily a result of changes in lens biomechanics. In particular, the shape of the ocular lens in the absence of zonular tension changes significantly throughout adulthood. Contributors to this change in shape are changes in lens biomechanical properties, continuous volumetric growth lens, and possibly remodeling of the lens capsule.

Tunable alginate hydrogels as injectable drug delivery vehicles for optic neuropathy.

Many disease pathologies, particularly in the eye, are induced by oxidative stress. In particular, injury to the optic nerve (ON), or optic neuropathy, is one of the most common causes of vision loss. Traumatic optic neuropathy (TON) occurs when the ON is damaged following blunt or penetrating trauma to either the head or eye.

A Pilot Randomized Trial of Heart Rate Monitoring Using Conventional Versus a New Electrocardiogram Algorithm during Neonatal Resuscitation at Birth.

Current guidelines support the use of a cardiac monitor during neonatal resuscitation. Infants born preterm randomized to a novel electrocardiogram algorithm displayed a heart rate sooner than the conventional electrocardiogram algorithm. Although resuscitation outcomes were not different, the availability of an earlier heart rate may benefit neonatal providers during high-risk resuscitations.

Outcomes of delivery room resuscitation of bradycardic preterm infants: A retrospective cohort study of randomised trials of high vs low initial oxygen concentration and an individual patient data analysis.

Objective: To determine whether hospital mortality (primary outcome) is associated with duration of bradycardia without chest compressions during delivery room (DR) resuscitation in a retrospective cohort study of randomized controlled trials (RCTs) in preterm infants assigned low versus high initial oxygen concentration.

Methods: Medline and EMBASE were searched from 01/01/1990 to 12/01/2020. RCTs of low vs high initial oxygen concentration which recorded serial heart rate (HR) and oxygen saturation (SpO) during resuscitation of infants <32 weeks gestational age were eligible.

Differential Alveolar and Systemic Oxygenation during Preterm Resuscitation with 100% Oxygen during Delayed Cord Clamping.

Objective: Delayed cord clamping (DCC) and 21 to 30% O resuscitation is recommended for preterm infants but is commonly associated with low pulmonary blood flow (Qp) and hypoxia. 100% O supplementation during DCC for 60 seconds followed by 30% O may increase Qp and oxygen saturation (SpO).

Study Design: Preterm lambs (125-127 days of gestation) were resuscitated with 100% O with immediate cord clamping (ICC,  = 7) or ICC + 30% O, and titrated to target SpO ( = 7) or DCC + 100% O for 60 seconds, which followed by cord clamping and 30% O titration ( = 7).

Association between early cerebral oxygenation and neurodevelopmental impairment or death in premature infants.

Objective: To assess the relationship between cerebral oxygenation in the first 72 h of life and neurodevelopmental impairment (NDI) at 2 years corrected age in former premature infants.

Study Design: Prospective observational cohort study of 127 infants <32 weeks GA at birth with cerebral oxygenation monitoring using NIRS in the first 72 h of life.

Results: Using a threshold cutoff for cerebral hypoxia, infants with NDI or death had increased duration of hypoxia (4 vs 2.

Multicentre, randomised trial of preterm infants receiving caffeine and less invasive surfactant administration compared with caffeine and early continuous positive airway pressure (CaLI trial): study protocol.

Introduction: Respiratory distress syndrome (RDS) or surfactant deficiency occurs primarily in premature infants resulting in composite outcomes of death or bronchopulmonary dysplasia. Initial management strategies for preterm infants with RDS includes early initiation of continuous positive airway pressure (CPAP) and titration of fractional inspired oxygen (FiO), and may include the use of less invasive surfactant administration (LISA) to avoid the need for mechanical ventilation. In order to optimise success of non-invasive support, the use of early caffeine therapy may be critical to the success of LISA.

Perinatal Outcomes of Subjects Enrolled in a Multicenter Trial with a Waiver of Antenatal Consent.

Objective: This study aimed to determine whether outcomes differed between infants enrolled in the PREMOD2 trial and those otherwise eligible but not enrolled, and whether the use of waiver effected these differences.

Study Design: The multicenter PREMOD2 (PREmature infants receiving Milking Or Delayed cord clamping) trial was approved for waiver of antenatal consent by six of the nine sites institutional review boards, while three sites exclusively used antenatal consent. Every randomized subject delivered at a site with a waiver of consent was approached for postnatal consent to allow for data collection.

Early Cardiac and Cerebral Hemodynamics with Umbilical Cord Milking Compared with Delayed Cord Clamping in Infants Born Preterm.

Objective: To evaluate changes in cerebral oxygenation, peripheral arterial oxygenation, respiratory status, and administered fraction of inspired oxygen during the first 10 minutes of life in premature infants receiving umbilical cord milking compared with delayed cord clamping (DCC).

Study Design: Premature infants born at 23 to 27 weeks of gestation were randomized to umbilical cord milking or DCC. A near infrared spectroscopy sensor, pulse oximeter, and electrocardiogram electrodes were placed.

Waived Consent in Perinatal/Neonatal Research-When Is It Appropriate?

Informed consent is a process ensuring that subjects enrolled in research are appropriately informed of the risks and benefits. While this process is well-defined when it is possible and practical to obtain consent prior to the research intervention, it can be less clear in cases of deferred or waived consent. Defining minimal risk, such as when research is attempting to determine which of two currently practiced interventions is safest and/or most effective, is critical to moving forward in establishing appropriate care in newborns.