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1.
PLoS One ; 15(5): e0231817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374734

RESUMO

Significant population declines in Acropora cervicornis and A. palmata began in the 1970s and now exceed over 90%. The losses were caused by a combination of coral disease and bleaching, with possible contributions from other stressors, including pollution and predation. Reproduction in the wild by fragment regeneration and sexual recruitment is inadequate to offset population declines. Starting in 2007, the Coral Restoration Foundation™ evaluated the feasibility of outplanting A. cervicornis colonies to reefs in the Florida Keys to restore populations at sites where the species was previously abundant. Reported here are the results of 20 coral outplanting projects with each project defined as a cohort of colonies outplanted at the same time and location. Photogrammetric analysis and in situ monitoring (2007 to 2015) measured survivorship, growth, and condition of 2419 colonies. Survivorship was initially high but generally decreased after two years. Survivorship among projects based on colony counts ranged from 4% to 89% for seven cohorts monitored at least five years. Weibull survival models were used to estimate survivorship beyond the duration of the projects and ranged from approximately 0% to over 35% after five years and 0% to 10% after seven years. Growth rate averaged 10 cm/year during the first two years then plateaued in subsequent years. After four years, approximately one-third of surviving colonies were ≥ 50 cm in maximum diameter. Projects used three to sixteen different genotypes and significant differences did not occur in survivorship, condition, or growth. Restoration times for three reefs were calculated based on NOAA Recovery Plan (NRP) metrics (colony abundance and size) and the findings from projects reported here. Results support NRP conclusions that reducing stressors is required before significant population growth and recovery will occur. Until then, outplanting protects against local extinction and helps to maintain genetic diversity in the wild.

2.
J Comp Neurol ; 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374025

RESUMO

Science and medicine aim to identify verifiable and replicable truths. However, the paths to such truths are frequently characterised by swinging pendulums of opposing perspectives. This is especially so in human neuroscience and the brain-based clinical sciences, where the target of investigation is the most complex of all biological systems. This paper overviews a set of interrelated neuroscientific and clinical hypotheses, models, experiments and predictions with which I have been involved for the last two decades. Traversing visual neuroscience, consciousness science, genetics, chronobiology, and biological and clinical psychiatry, the work illustrates how developments in science and medicine can occur through a combination of synthesis, serendipity and experimentation. The paper also reflects on doing science with the inimitable John 'Jack' Pettigrew, and outlines how Pettigrew and I conceived, proposed, tested and developed two new scientific models - one on neural mechanisms of binocular rivalry, the other on the pathophysiology of bipolar disorder. I also provide an update on various aspects of our models and data, and describe lessons learned from Pettigrew on how perspectives in science exhibit their own fluctuations, ironically like the very phenomena on which we worked.

3.
Opt Lett ; 45(7): 1934-1937, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236036

RESUMO

Compact beam steering in the visible spectral range is required for a wide range of emerging applications, such as augmented and virtual reality displays, optical traps for quantum information processing, biological sensing, and stimulation. Optical phased arrays (OPAs) can shape and steer light to enable these applications with no moving parts on a compact chip. However, OPA demonstrations have been mainly limited to the near-infrared spectral range due to the fabrication and material challenges imposed by the shorter wavelengths. Here, we demonstrate the first chip-scale phased array operating at blue wavelengths (488 nm) using a high-confinement silicon nitride platform. We use a sparse aperiodic emitter layout to mitigate fabrication constraints at this short wavelength and achieve wide-angle beam steering over a 50° field of view with a full width at half-maximum beam size of 0.17°. Large-scale integration of this platform paves the way for fully reconfigurable chip-scale three-dimensional volumetric light projection across the entire visible range.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32195905

RESUMO

OBJECTIVES: The aims of this study were to: i) determine the spectrum of brain injury and ii) compare brain volumes between pre- and postoperative brain MRI in the infants receiving extracorporeal membrane oxygenation compared with those who did not require extracorporeal membrane oxygenation. DESIGN: Cohort study of infants with D-transposition of the great arteries or single ventricle physiology. Brain volume (cm) was measured using a segmentation of a volumetric T1-weighted gradient echo sequence. Brain imaging findings (intraventricular hemorrhage, white matter injuries, and stroke) were analyzed with respect to known clinical risk factors for brain injury and adverse neurodevelopmental outcomes. Clinical factors were collected by retrospective chart review. The association between brain volume and extracorporeal membrane oxygenation was evaluated using generalized estimating equations to account for repeated measures. SETTING: Prospective and single-centered study. PATIENTS: One hundred nine infants (median gestational age, 39.1 wk) with D-transposition of the great arteries (n = 77) or single ventricle physiology (n = 32) were studied pre- and postoperatively with MRI as per clinical protocol. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 28 infants (26%) receiving extracorporeal membrane oxygenation, 19 (68%) were supported with extracorporeal membrane oxygenation once, and nine (32%) were supported 2-4 times. On postoperative MRI, new white matter injury was found in only five (17%) of the extracorporeal membrane oxygenation infants versus 40 (49%) in the non-extracorporeal membrane oxygenation group (p = 0.073). The rate of stroke (9% vs 10%), intraventricular hemorrhage (24% vs 29%), and hypoxic ischemia (3% vs 14%) did not differ between the non-extracorporeal membrane oxygenation and extracorporeal membrane oxygenation groups (all p > 0.5). Accounting for D-transposition of the great arteries or single ventricle physiology diagnosis, infants requiring extracorporeal membrane oxygenation had slower brain volume with single (ß = -1.67) or multiple extracorporeal membrane oxygenation runs ([ß = -6.54]; overall interaction p = 0.012). CONCLUSIONS: Patients with d-transposition of the great arteries or single ventricle physiology undergoing extracorporeal membrane oxygenation at our center have a similar incidence of brain injury but more significant impairment of perioperative brain volumes than those not requiring extracorporeal membrane oxygenation.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32196785

RESUMO

OBJECTIVE: Septo-optic dysplasia (SOD) is a clinical syndrome characterized by varying combinations of optic nerve hypoplasia, pituitary gland hypoplasia and abnormal cavum septum pellucidum. It is suspected on prenatal imaging when there is non-visualization or hypoplasia of the septal leaflets. Long-term postnatal outcomes of fetuses with prenatally suspected SOD have been poorly documented. Our aims were to describe the natural history of deficient septal leaflets, to quantify the incidence of postnatally confirmed SOD, and to document the long-term visual, endocrine and neurodevelopmental outcomes of these infants. METHODS: An observational retrospective study of all fetuses with prenatal imaging showing isolated septal agenesis, assessed at a single tertiary centre over a 10-year period. Pregnancy, delivery, pre- and postnatal imaging and neonatal outcomes were reviewed for clinical confirmation of SOD. Long-term ophthalmologic, endocrine, developmental and genetic evaluations were assessed. RESULTS: Of 214 fetuses presenting with septal absence on US and MRI, 18 (8.4%) were classified as suspected isolated septal agenesis concerning for SOD. Uniform prenatal MRI findings of suspected SOD included remnants of the septal leaflets of the cavum, fused forniceal columns, normal olfactory bulbs and tracts and a normal optic chiasm. Twelve fetuses were liveborn and five (27.8%) had postnatally confirmed SOD. Only two of these five had additional prenatal imaging features (pituitary cyst, microphthalmia and optic nerve hypoplasia) supporting a diagnosis of SOD. The other three confirmed SOD cases had no predictive prenatal or postnatal imaging findings which reliably differentiated between infants with and without confirmed SOD. At a median follow-up of 2.5 (2.5,7) years, visual and endocrine impairment were present in two (40%) and four (80%) cases, respectively. In those with visual and or endocrine impairment, developmental delay was common (80%) and mostly severe. Neonates with isolated septal agenesis and lack of visual or endocrine abnormalities to confirm SOD had normal development. CONCLUSION: Only a quarter of individuals with isolated septal agenesis suggestive of SOD will have postnatal confirmation of the diagnosis. Clinical manifestations of SOD are variable, but neurodevelopmental delay may be more prevalent than formerly thought. This article is protected by copyright. All rights reserved.

7.
Pediatr Res ; 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32172281

RESUMO

BACKGROUND: Several factors contribute to neurodevelopmental outcomes in preterm infants. The aim of this study was to examine the genetic and environmental influences on long-term outcomes in preterm twins. METHODS: From a prospective cohort of 225 preterm neonates studied with MRI, 24 monozygotic and 52 dizygotic twins were included. Neurodevelopmental outcomes at 1.5 and 3 years were assessed with the Bayley-III and at 4.5 years with The Movement Assessment Battery for Children and The Wechsler Preschool and Primary Scale of Intelligence-III. RESULTS: Preterm monozygotic and dizygotic twin pairs (N = 76 neonates) had similar neurodevelopmental outcomes at all time points. Monozygotic twins (N = 24) did not show greater agreement for outcomes relative to dizygotic twins (N = 52). Twin pairs who were discordant in development (N = 12) were born at a lower gestational age and had a higher incidence of bronchopulmonary dysplasia and retinopathy of prematurity. Discordant twins become more similar in cognitive and language outcomes over time. CONCLUSIONS: Neurodevelopmental outcomes in preterm twins may relate more strongly to environmental factors than genetics. Discordant twins were born earlier and had more perinatal morbidities. Despite the initial discordance, these twin pairs become similar in outcomes over time, which may reflect the positive impact of home environment or early intervention programs. IMPACT: Neurodevelopmental outcomes in preterm twins relate more strongly to environmental factors than genetics. Monozygotic twins did not show greater agreement in outcomes relative to dizygotic twins suggesting a stronger environmental, rather than genetic, influence on development. Twin pairs who were discordant in development were born at a lower gestational age and had a higher incidence of perinatal morbidities. Despite the initial discordance, these twin pairs become more similar in cognitive and language outcomes over time, which may reflect the positive impact of early intervention programs or home environment. Neurodevelopmental outcomes in preterm twins are influenced by exposure to early-life insults or environmental stressors. The initial variability in outcomes among preterm infants is not fixed, and efforts made post-discharge from the neonatal intensive care unit can have a substantial impact on long-term outcomes.

10.
Nat Biomed Eng ; 4(2): 223-231, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051578

RESUMO

The use of nanophotonics to rapidly and precisely reconfigure light beams for the optical stimulation of neurons in vivo has remained elusive. Here we report the design and fabrication of an implantable silicon-based probe that can switch and route multiple optical beams to stimulate identified sets of neurons across cortical layers and simultaneously record the produced spike patterns. Each switch in the device consists of a silicon nitride waveguide structure that can be rapidly (<20 µs) reconfigured by electrically tuning the phase of light. By using an eight-beam probe, we show in anaesthetized mice that small groups of single neurons can be independently stimulated to produce multineuron spike patterns at sub-millisecond precision. We also show that a probe integrating co-fabricated electrical recording sites can simultaneously optically stimulate and electrically measure deep-brain neural activity. The technology is scalable, and it allows for beam focusing and steering and for structured illumination via beam shaping. The high-bandwidth optical-stimulation capacity of the device might facilitate the probing of the spatiotemporal neural codes underlying behaviour.


Assuntos
Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/métodos , Hipocampo/fisiologia , Nanotecnologia , Neurônios/fisiologia , Córtex Visual/fisiologia , Potenciais de Ação , Animais , Desenho de Equipamento , Feminino , Camundongos Transgênicos , Processamento de Sinais Assistido por Computador , Silício
11.
Pediatr Res ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896130

RESUMO

Preterm infants are exposed to frequent painful procedures and agitating stimuli over the many weeks of their hospitalization in the neonatal intensive care unit (NICU). The adverse neurobiological impact of pain and stress in the preterm infant has been well documented, including neuroimaging and neurobehavioral outcomes. Although many tools have been validated to assess acute pain, few methods are available to assess chronic pain or agitation (a clinical manifestation of neonatal stress). Both nonpharmacologic and pharmacologic approaches are used to reduce the negative impact of pain and agitation in the preterm infant, with concerns emerging over the adverse effects of analgesia and sedatives. Considering benefits and risks of available treatments, units must develop a stepwise algorithm to prevent, assess, and treat pain. Nonpharmacologic interventions should be consistently utilized prior to mild to moderately painful procedures. Sucrose may be utilized judiciously as an adjunctive therapy for minor painful procedures. Rapidly acting opioids (fentanyl or remifentanil) form the backbone of analgesia for moderately painful procedures. Chronic sedation during invasive mechanical ventilation represents an ongoing challenge; appropriate containment and an optimal environment should be standard; when indicated, low-dose morphine infusion may be utilized cautiously and dexmedetomidine infusion may be considered as an emerging adjunct.

12.
Pediatr Res ; 87(2): 391-398, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31666689

RESUMO

Improved intensive care therapies have increased the survival of children born preterm. Yet, many preterm children experience long-term neurodevelopmental sequelae. Indeed, preterm birth remains a leading cause of lifelong neurodevelopmental disability globally, posing significant challenges to the child, family, and society. Neurodevelopmental disability in children born preterm is traditionally linked to acquired brain injuries such as white matter injury and to impaired brain maturation resulting from neonatal illness such as chronic lung disease. Socioeconomic status (SES) has long been recognized to contribute to variation in outcome in children born preterm. Recent brain imaging data in normative term-born cohorts suggest that lower SES itself predicts alterations in brain development, including the growth of the cerebral cortex and subcortical structures. Recent evidence in children born preterm suggests that the response to early-life brain injuries is modified by the socioeconomic circumstances of children and families. Exciting new data points to the potential of more favorable SES circumstances to mitigate the impact of neonatal brain injury. This review addresses emerging evidence suggesting that SES modifies the relationship between early-life exposures, brain injury, and neurodevelopmental outcomes in children born preterm. Better understanding these relationships opens new avenues for research with the ultimate goal of promoting optimal outcomes for those children born preterm at highest risk of neurodevelopmental consequence.

13.
N Z Med J ; 132(1504): 13-23, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31647791

RESUMO

AIMS: To compare the outcome of people with type 1 diabetes admitted to the general ward with diabetic ketoacidosis (DKA) to two hospitals in Auckland, using different protocols of care. METHODS: North Shore Hospital uses a UK weight-based, ketone centric protocol while Auckland Hospital uses a protocol based on glucose measurements only. All notes of people over 16 years of age admitted to the general wards with DKA to these hospitals in one year were reviewed and their outcome compared. RESULTS: Forty-one admissions in 35 people with DKA at Auckland Hospital were compared to 30 admissions in 26 people with DKA at North Shore Hospital. The degree of ketoacidosis and hyperglycaemia on admission was similar at the two hospitals. The duration of insulin and 10% dextrose infusions was similar but the total number of units of insulin infused and rate of dextrose given per hour were higher at North Shore, with similar rates of hypokalaemia and hypoglycaemic events at each site. The rate of resolution of hyperglycaemia and acidosis did not differ. The length of stay of patients was similar at the two hospitals. CONCLUSIONS: The frequent measurement of bedside ketones did not result in more rapid resolution of DKA compared to relying on glucose measurements alone.

14.
Nutrients ; 11(9)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480225

RESUMO

Extremely preterm babies are at increased risk of less than optimal neurodevelopment compared with their term-born counterparts. Optimising nutrition is a promising avenue to mitigate the adverse neurodevelopmental consequences of preterm birth. In this narrative review, we summarize current knowledge on how nutrition, and in particular, protein intake, affects neurodevelopment in extremely preterm babies. Observational studies consistently report that higher intravenous and enteral protein intakes are associated with improved growth and possibly neurodevelopment, but differences in methodologies and combinations of intravenous and enteral nutrition strategies make it difficult to determine the effects of each intervention. Unfortunately, there are few randomized controlled trials of nutrition in this population conducted to determine neurodevelopmental outcomes. Substantial variation in reporting of trials, both of nutritional intakes and of outcomes, limits conclusions from meta-analyses. Future studies to determine the effects of nutritional intakes in extremely preterm babies need to be adequately powered to assess neurodevelopmental outcomes separately in boys and girls, and designed to address the many potential confounders which may have clouded research findings to date. The development of minimal reporting sets and core outcome sets for nutrition research will aid future meta-analyses.


Assuntos
Encéfalo/crescimento & desenvolvimento , Desenvolvimento Infantil , Deficiências do Desenvolvimento/prevenção & controle , Nutrição Enteral/métodos , Lactente Extremamente Prematuro/crescimento & desenvolvimento , Feminino , Humanos , Recém-Nascido , Masculino
15.
Elife ; 82019 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-31545167

RESUMO

Suppressor of Hairless [Su(H)], the transcription factor at the end of the Notch pathway in Drosophila, utilizes the Hairless protein to recruit two co-repressors, Groucho (Gro) and C-terminal Binding Protein (CtBP), indirectly. Hairless is present only in the Pancrustacea, raising the question of how Su(H) in other protostomes gains repressive function. We show that Su(H) from a wide array of arthropods, molluscs, and annelids includes motifs that directly bind Gro and CtBP; thus, direct co-repressor recruitment is ancestral in the protostomes. How did Hairless come to replace this ancestral paradigm? Our discovery of a protein (S-CAP) in Myriapods and Chelicerates that contains a motif similar to the Su(H)-binding domain in Hairless has revealed a likely evolutionary connection between Hairless and Metastasis-associated (MTA) protein, a component of the NuRD complex. Sequence comparison and widely conserved microsynteny suggest that S-CAP and Hairless arose from a tandem duplication of an ancestral MTA gene.


Assuntos
Anelídeos/genética , Artrópodes/genética , Evolução Molecular , Moluscos/genética , Transdução de Sinais , Fatores de Transcrição/genética , Animais , Fatores de Transcrição/metabolismo
18.
Neurology ; 93(13): e1231-e1240, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31467250

RESUMO

OBJECTIVE: To develop a simple imaging rule to predict neurodevelopmental outcomes at 4.5 years in a cohort of preterm neonates with white matter injury (WMI) based on lesion location and examine whether clinical variables enhance prediction. METHODS: Sixty-eight preterm neonates born 24-32 weeks' gestation (median 27.7 weeks) were diagnosed with WMI on early brain MRI scans (median 32.3 weeks). 3D T1-weighted images of 60 neonates with 4.5-year outcomes were reformatted and aligned to the posterior commissure-eye plane and WMI was classified by location: anterior or posterior-only to the midventricle line on the reformatted axial plane. Adverse outcomes at 4.5 years were defined as Wechsler Preschool and Primary Scale of Intelligence full-scale IQ <85, cerebral palsy, or Movement Assessment Battery for Children, second edition percentile <5. The prediction of adverse outcome by WMI location, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP) was assessed using multivariable logistic regression. RESULTS: Six children had adverse cognitive outcomes and 17 had adverse motor outcomes. WMI location predicted cognitive outcomes in 90% (area under receiver operating characteristic curve [AUC] 0.80) and motor outcomes in 85% (AUC 0.75). Adding IVH, BPD, and ROP to the model enhances the predictive strength for cognitive and motor outcomes (AUC 0.83 and 0.88, respectively). Rule performance was confirmed in an independent cohort of children with WMI. CONCLUSIONS: WMI on early MRI can be classified by location to predict preschool age outcomes in children born preterm. The predictive value of this WMI classification is enhanced by considering clinical factors apparent by term-equivalent age.


Assuntos
Lesões Encefálicas/patologia , Encéfalo/crescimento & desenvolvimento , Lactente Extremamente Prematuro/crescimento & desenvolvimento , Substância Branca/patologia , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Imagem por Ressonância Magnética/métodos , Masculino , Substância Branca/crescimento & desenvolvimento
19.
Appl Clin Inform ; 10(4): 634-642, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31461754

RESUMO

OBJECTIVE: The Leadership in Analytics and Data Science (LEADS) course was evaluated for effectiveness. LEADS was a 6-month program for working biomedical and health informatics (BMHI) professionals designed to improve analytics skills, knowledge of enterprise applications, data stewardship, and to foster an analytics community of practice through lectures, hands-on skill building workshops, networking events, and small group projects. METHODS: The effectiveness of the LEADS course was evaluated using the Kirkpatrick Model by assessing pre- and postcourse knowledge, analytics capabilities, goals, practice, class lecture reaction, and change in the size of participant professional networks. Differences in pre- and postcourse responses were analyzed with a Wilcoxon signed rank test to determine significance, and effect sizes were computed using a z-statistic. RESULTS: Twenty-nine students completed the course with 96% of respondents reporting that they were "very" or "extremely" likely to recommend the course. Participants reported improvement in several analytics capabilities including Epic data warehousing (p = 0.017), institutional review board policy (p = 0.005), and data stewardship (p = 0.007). Changes in practice patterns mirrored those in self-reported capability. On average, the participant professional network doubled. CONCLUSION: LEADS was the first course targeted to working BMHI professional at a large academic medical center to have a formal effectiveness evaluation be published in the literature. The course achieved the goals of expansion of BMHI knowledge, skills, and professional networks. The LEADS course provides a template for continuing education of working BMHI professionals.

20.
J Pediatr ; 215: 75-82.e2, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31451185

RESUMO

OBJECTIVES: To determine prevalence and risk factors for brain injury in infants with critical congenital heart disease (CHD) from 2 sites with different practice approaches who were scanned clinically. STUDY DESIGN: Prospective, longitudinal cohort study (2016-2017) performed at Hospital for Sick Children Toronto (HSC) and Wilhelmina Children's Hospital Utrecht (WKZ), including 124 infants with cardiac surgery ≤60 days (HSC = 77; WKZ = 47). Magnetic resonance imaging was performed per clinical protocol, preoperatively (n = 100) and postoperatively (n = 120). Images were reviewed for multifocal (watershed, white matter injury) and focal ischemic injury (stroke, single white matter lesion). RESULTS: The prevalence of ischemic injury was 69% at HSC and 60% at WKZ (P = .20). Preoperative multifocal injury was associated with low cardiac output syndrome (OR, 4.6), which was equally present at HSC and WKZ (20% vs 28%; P = .38). Compared with WKZ, HSC had a higher prevalence of balloon-atrioseptostomy in transposition of the great arteries (83% vs 53%; P = .01) and more frequent preoperative focal injury (27% vs 6%; P = .06). Postoperatively, 30% of new multifocal injury could be attributed to postoperative low cardiac output syndrome, which was equally present at HSC and WKZ (38% vs 28%; P = .33). Postoperative focal injury was associated with intraoperative selective cerebral perfusion in CHD with arch obstruction at both sites (OR, 2.7). Compared with HSC, WKZ had more arch obstructions (62% vs 35%; P < .01) and a higher prevalence of new focal injury (36% vs 16%; P = .01). CONCLUSIONS: Brain injury is common in clinical cohorts of infants with critical CHD and related to practice approaches. This study confirms that the high prevalence of brain injury in critical CHD is a clinical concern and does not simply reflect the inclusion criteria of published research studies.

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