Excessive fine sediment (particles <2 mm) deposition in freshwater systems is a pervasive stressor worldwide. However, understanding of ecological response to excess fine sediment in river systems at the global scale is limited. Here, we aim to address whether there is a consistent response to increasing levels of deposited fine sediment by freshwater invertebrates across multiple geographic regions (Australia, Brazil, New Zealand and the UK). Results indicate ecological responses are not globally consistent and are instead dependent on both the region and the facet of invertebrate diversity considered, that is, taxonomic or functional trait structure. Invertebrate communities of Australia were most sensitive to deposited fine sediment, with the greatest rate of change in communities occurring when fine sediment cover was low (below 25% of the reach). Communities in the UK displayed a greater tolerance with most compositional change occurring between 30% and 60% cover. In both New Zealand and Brazil, which included the most heavily sedimented sampled streams, the communities were more tolerant or demonstrated ambiguous responses, likely due to historic environmental filtering of invertebrate communities. We conclude that ecological responses to fine sediment are not generalisable globally and are dependent on landscape filters with regional context and historic land management playing important roles.
The zebra mussel Dreissena polymorpha is one of the most successful, notorious, and detrimental aquatic invasive non‐native species worldwide, having invaded Europe and North America while causing substantial ecological and socio‐economic impacts. Here, we investigated the spatiotemporal trends in this species' invasion success using 178 macroinvertebrate abundance time series, containing 1451 records of D. polymorpha collected across nine European countries between 1972–2019. Using these raw (absolute) abundance data, we examined trends and drivers of occurrences and relative abundances of D. polymorpha within invaded communities. Meta‐regression models revealed non‐significant trends both at the European level and for the majority of the invaded countries, except for France (significant decreasing trend) and Hungary (marginally positive trend). At the European level, the number of D. polymorpha occurrences over time followed a flat‐top bell‐shaped distribution, with a steep increase between 1973–1989 followed by a plateau phase prior to significantly declining post‐1998. Using a series of climatic and hydromorphological site‐specific characteristics of invaded and uninvaded sites from two periods (1998–2002; 2011–2015), we found that native richness, non‐native abundance, distance to the next barrier, and elevation were associated with the occurrence of D. polymorpha . We also found that higher native richness and lower latitude were related to lower relative abundances. Using Cohen's D as a measure of D. polymorpha impact, we found that biodiversity within the invaded sites was initially higher than in uninvaded ones, but then declined, suggesting differences in biodiversity trends across invaded and uninvaded sites. While our results emphasise the high invasion success of D. polymorpha , increasing stressors within the context of global change – particularly ongoing climate change – are likely to enhance invasion rates and the impact of D. polymorpha in the near future, exacerbated by the lack of timely and effective management actions.
AimTo determine which riverine invertebrate traits respond consistently to anthropogenic impacts across multiple biogeographic regions.LocationEurope.Time Period1981-2021.Major Taxa StudiedRiverine invertebrates.MethodsWe compiled a database of riverine invertebrate community time series for 673 sites across six European countries spanning six freshwater ecoregions. We compared trait responses to anthropogenic impacts (quantified as changes in 'ecological quality') among regions for seven 'ecological' traits, which reflect habitat preferences, and nine 'biological' traits (e.g., morphology or life history), which represent taxon-specific attributes that can influence ecosystem processes.ResultsFour ecological traits (current, microhabitat, salinity and trophic preferences) and one biological trait (dispersal mode) responded consistently across regions. These responses were primarily driven by spatial differences among poorer to better quality sites. Responses to temporal changes in quality were comparable but less pronounced.Main ConclusionsConsistent responses to anthropogenic impacts across multiple ecological traits indicate these traits may improve broader scale measurements, comparisons and predictions of community responses. However, we could not use ecological traits to identify the actions of specific stressors because multiple traits always responded as a group. Inconsistent responses across almost all biological traits indicated that these traits may be less predictive of impacts across regions. Predictions of how biological traits, and associated ecosystem processes, respond to anthropogenic impacts may be most effective at regional scales where responses are more consistent.
Freshwater macroinvertebrates are a diverse group and play key ecological roles, including accelerating nutrient cycling, filtering water, controlling primary producers, and providing food for predators. Their differences in tolerances and short generation times manifest in rapid community responses to change. Macroinvertebrate community composition is an indicator of water quality. In Europe, efforts to improve water quality following environmental legislation, primarily starting in the 1980s, may have driven a recovery of macroinvertebrate communities. Towards understanding temporal and spatial variation of these organisms, we compiled the TREAM dataset (Time seRies of European freshwAter Macroinvertebrates), consisting of macroinvertebrate community time series from 1,816 river and stream sites (mean length of 19.2 years and 14.9 sampling years) of 22 European countries sampled between 1968 and 2020. In total, the data include >93 million sampled individuals of 2,648 taxa from 959 genera and 212 families. These data can be used to test questions ranging from identifying drivers of the population dynamics of specific taxa to assessing the success of legislative and management restoration efforts.
ObjectivesScientific evidence provides a widened view of differences in immune response between male and female neonates. The X-chromosome codes for several genes important in the innate immune response and neonatal innate immune cells express receptors for, and are inhibited by, maternal sex hormones. We hypothesized that sex differences in innate immune responses may be present in the neonatal population which may contribute to the increased susceptibility of premature males to sepsis. We aimed to examine the in vitro effect of pro-inflammatory stimuli and hormones in neutrophils and monocytes of male and female neonates, to examine the expression of X-linked genes involved in innate immunity and the miRNA profiles in these populations.MethodsPreterm infants (n = 21) and term control (n = 19) infants were recruited from the Coombe Women and Infants University Hospital Dublin with ethical approval and explicit consent. The preterm neonates (eight female, 13 male) were recruited with a mean gestation at birth (mean +/- SD) of 28 +/- 2 weeks and corrected gestation at the time of sampling was 30 + 2.6 weeks. The mean birth weight of preterm neonates was 1084 +/- 246 g. Peripheral blood samples were used to analyze immune cell phenotypes, miRNA human panel, and RNA profiles for inflammasome and inflammatory genes.ResultsDividing neutrophil results by sex showed no differences in baseline CD11b between sexes among either term or preterm neonates. Examining monocyte CD11b by sex shows, that at baseline, total and classical monocytes have higher CD11b in preterm females than preterm males. Neutrophil TLR2 did not differ between sexes at baseline or following lipopolysaccharide (LPS) exposure. CD11b expression was higher in preterm male non-classical monocytes following Pam3CSK treatment when compared to females, a finding which is unique to our study. Preterm neonates had higher TLR2 expression at baseline in total monocytes, classical monocytes and non-classical monocytes than term. A sex difference was evident between preterm females and term females in TLR2 expression only. Hormone treatment showed no sex differences and there was no detectable difference between males and females in X-linked gene expression. Two miRNAs, miR-212-3p and miR-218-2-3p had significantly higher expression in preterm female than preterm male neonates.ConclusionsThis study examined immune cell phenotypes and x-linked gene expression in preterm neonates and stratified according to gender. Our findings suggest that the responses of females mature with advancing gestation, whereas male term and preterm neonates have very similar responses. Female preterm neonates have improved monocyte activation than males, which likely reflects improved innate immune function as reflected clinically by their lower risk of sepsis. Dividing results by sex showed changes in preterm and term infants at baseline and following LPS stimulation, a difference which is reflected clinically by infection susceptibility. The sex difference noted is novel and may be limited to the preterm or early neonatal population as TLR2 expression on monocytes of older children does not differ between males and females. The differences shown in female and male innate immune cells likely reflect a superior innate immune defense system in females with sex differences in immune cell maturation. Existing human studies on sex differences in miRNA expression do not include preterm patients, and most frequently use either adult blood or cord blood. Our findings suggest that miRNA profiles are similar in neonates of opposite sexes at term but require further investigation in the preterm population. Our findings, while novel, provide only very limited insights into sex differences in infection susceptibility in the preterm population leaving many areas that require further study. These represent important areas for ongoing clinical and laboratory study and our findings represent an important contribution to exiting literature.
Monitoring programmes worldwide use biota to assess the "health" of water bodies. Indices based on biota are used to describe the change in status of sites over time, to identify progress against management targets and to diagnose the causes of biological degradation. A variety of numerical stressor-specific biotic indices have been developed based on the response of biota to differences in stressors among sites. Yet, it is not clear how variation in pressures within sites, over what time period, and in what combination has the greatest impact on different biotic groups. An understanding of how temporal variation in pressures influences biological assessment indices would assist in setting achievable targets and help focus catchment-scale mitigation strategies to ensure that they deliver the desired improvements in biological condition. Hydrochemical data provided by a network of high-frequency (15 or 30 min) automated monitoring stations over 3 years were matched to replicated biological data to understand the influence of spatio-temporal variation in pollution pressures on biological indices. Hydrochemical data were summarised in various ways to reflect central tendency, peaks, troughs and variation over 1-90 days before the collection of each biological sample. An objective model selection procedure was used to determine which hydrochemical determinand, and over what time period, best explained variation in the biological indices. Stressor-specific indices derived from macroinvertebrates which purportedly assess stress from low flows, excess fine sediment, nutrient enrichment, pesticides and organic pollution were significantly inter-correlated and reflected periods of low oxygen concentration, even though only one index (ASPT(WHPT), average score per taxon) was designed for this purpose. Changes in community composition resulting from one stressor frequently lead to confounding effects on stressor-specific indices. Variation in ASPT(WHPT) was best described by dissolved oxygen calculated as Q(5) over 10 days, suggesting that low oxygen events had most influence over this period. Longer-term effects were apparent, but were masked by recovery. Macroinvertebrate abundance was best described by Q(95) of stream velocity over 60 days, suggesting a slower recovery in numbers than in the community trait reflected by ASPT(WHPT). Although use of ASPT(WHPT) was supported, we recommend that additional independent evidence should be used to corroborate any conclusions regarding the causes of degradation drawn from the other stressor-specific indices. The use of such stressor-specific indices alone risks the mistargeting of management strategies if the putative stressor-index approach is taken to be more reliable than the results herein suggest.
Non-native species introductions have been acknowledged as one of the main drivers of freshwater biodiversity decline worldwide, compromising provided ecosystem services and functioning. Despite growing introduction numbers of non-native species, their impacts in conjunction with anthropogenic stressors remain poorly documented. To fill this gap, we studied temporal changes in α (local scale) and γ (regional scale), as well as β (ratio between γ and α) diversity of non-native freshwater macroinvertebrate species in three European countries (the Netherlands, England and Hungary) using long-term time series data of up to 17 years (2003-2019). We further calculated four ecological and four biological trait metrics to identify changes in trait occurrences over time. We found that α and γ diversities of non-native species were increasing across all countries whereas β diversity remained stable. We did not identify any significant changes in any trait metric over time, while the predictors tested (land use, climatic predictors, site-specific factor) were similar across countries (e.g., site characteristics or climatic predictors on non-native species trends). Additionally, we projected trends of α, β, and γ diversity and trait metrics until 2040, which indicated that non-native species will decline across all countries to lower levels except in England for γ diversity and the Netherlands for α diversity where an increase was observed. Thus, our findings indicate shifts in non-native freshwater macroinvertebrate diversity at both local and regional scales in response to the various growing anthropogenic pressures. Our findings underscore the continuous dynamics of non-native species distribution, with the diversity of individual communities and overall landscapes witnessing changes. However, the differentiation in species composition between communities remains unaltered. This could have profound implications for conservation strategies and ecological management in the face of continuously changing biodiversity patterns.
The use of long-term datasets is crucial in ecology because it provides a comprehensive understanding of natural fluctuations, changes in ecosystems over extended periods of time, and robust comparisons across geographical scales. This information is critical in detecting and analysing trends and patterns in species populations, community dynamics, and ecosystem functioning, which in turn helps in predicting future changes and impacts of human activities. Additionally, long-term data sets allow for the evaluation of the effectiveness of conservation efforts and management strategies, enabling scientists and decision makers to make evidence-based decisions for biodiversity conservation. Although the use of long-term data is recognized as highly important in several scientific disciplines, its usage remains undervalued regarding questions in invasion science. Here, we used four regional subsets (i.e. England, Hungary, Denmark and the Dutch-German-Luxembourg) of a recently collated long-term time series database to investigate the abundance and dynamics of occurring non-native species over space and time in Europe. While we found differences in the numbers of non-native species across the studied regions (Dutch-German-Luxembourg region = 37; England = 17, Hungary = 34; Denmark = 3), non-native species detection rates were continuous over time. Our results further show that long-term monitoring efforts at large spatial scales can substantially increase the accuracy and rate at which non-native species are detected. This information can inform management endeavours dealing with non-native species, underlining the need for invasion scientists and authorities-stakeholders to make more effort in collecting, analysing and making available long-term datasets at broader geographic ranges.
As alien invasive species are a key driver of biodiversity loss, understanding patterns of rapidly changing global species compositions depends upon knowledge of invasive species population dynamics and trends at large scales. Within this context, the Ponto-Caspian region is among the most notable donor regions for aquatic invasive species in Europe. Using macroinvertebrate time series collected over 52 years (1968–2020) at 265 sites across 11 central and western European countries, we examined the occurrences, invasion rates, and abundances of freshwater Ponto-Caspian fauna. We examined whether: (i) successive Ponto-Caspian invasions follow a consistent pattern of composition pioneered by the same species, and (ii) Ponto-Caspian invasion accelerates subsequent invasion rates. In our dataset, Ponto-Caspian macroinvertebrates increased from two species in 1972 to 29 species in 2012. This trend was parallelled by a non-significant increasing trend in the abundances of Ponto-Caspian taxa. Trends in Ponto-Caspian invader richness increased significantly over time. We found a relatively uniform distribution of Ponto-Caspian macroinvertebrates across Europe without any relation to the distance to their native region. The Ponto-Caspian species that arrived first were often bivalves (46.5% of cases), particularly Dreissena polymorpha , followed secondarily by amphipods (83.8%; primarily Chelicorophium curvispinum and Dikerogammarus villosus ) . The time between consecutive invasions decreased significantly at our coarse regional scale, suggesting that previous alien establishments may facilitate invasions of subsequent taxa. Should alien species continue to translocate from the Ponto-Caspian region, our results suggest a high potential for their future invasion success highly connected central and western European waters. However, each species’ population may decline after an initial ‘boom’ phase or after the arrival of new invasive species, resulting in different alien species dominating over time.
Owing to a long history of anthropogenic pressures, freshwater ecosystems are among the most vulnerable to biodiversity loss 1 . Mitigation measures, including wastewater treatment and hydromorphological restoration, have aimed to improve environmental quality and foster the recovery of freshwater biodiversity 2 . Here, using 1,816 time series of freshwater invertebrate communities collected across 22 European countries between 1968 and 2020, we quantified temporal trends in taxonomic and functional diversity and their responses to environmental pressures and gradients. We observed overall increases in taxon richness (0.73% per year), functional richness (2.4% per year) and abundance (1.17% per year). However, these increases primarily occurred before the 2010s, and have since plateaued. Freshwater communities downstream of dams, urban areas and cropland were less likely to experience recovery. Communities at sites with faster rates of warming had fewer gains in taxon richness, functional richness and abundance. Although biodiversity gains in the 1990s and 2000s probably reflect the effectiveness of water-quality improvements and restoration projects, the decelerating trajectory in the 2010s suggests that the current measures offer diminishing returns. Given new and persistent pressures on freshwater ecosystems, including emerging pollutants, climate change and the spread of invasive species, we call for additional mitigation to revive the recovery of freshwater biodiversity.
Introduction: Melatonin has been suggested an adjunctive therapy in neonatal encephalopathy (NE). Melatonin reduces oxidative stress and neutrophil activation; however, the immunological effects in NE have not been studied. Methods: Infants with NE and neonatal controls were prospectively recruited. Whole blood was sampled in the first week of life. Following endotoxin and or melatonin treatment, diurnal variation was measured by RT PCR for circadian rhythm genes (brain and Muscle Arnt-Like protein [BMAL1], circadian locomotor output cycles kaput [CLOCK], Nuclear Receptor Subfamily 1 Group D Member 2 [REV Erβ], and cryptochrome circadian clock [CRY]). Neutrophil and monocyte cell surface markers of activation CD11b, reactive oxygen intermediates (ROIs), and Toll-like receptor (TLR)-4 were also examined by flow cytometry in matching samples. Results: Serum and RNA samples from forty infants were included (controls n = 20; NE n = 20) over the first week of life. Melatonin reduced neutrophil CD11b and TLR-4 expression in response to LPS in infants with NE compared to controls. There were no differences in ROIs. BMAL1 and CLOCK baseline gene expression levels were similar. BMAL1 was significantly decreased with LPS stimulation in NE. There was no significant diurnal variation in melatonin, neutrophil, and monocyte function or circadian genes. Conclusions: Melatonin alters immune function ex vivo in infants with NE. Infants with NE have altered immune circadian responses following LPS stimulation, which have potential for modulation.
Europe has experienced a substantial increase in non-indigenous crayfish species (NICS) since the mid-20th century due to their extensive use in fisheries, aquaculture and, more recently, pet trade. Despite relatively long invasion histories of some NICS and negative impacts on biodiversity and ecosystem functioning, large spatio-temporal analyses of their occurrences are lacking. Here, we used a large freshwater macroinvertebrate database to evaluate what information on NICS can be obtained from widely applied biomonitoring approaches and how usable such data is for descriptions of trends in identified NICS species. We found 160 time-series containing NICS between 1983 and 2019, to infer temporal patterns and environmental drivers of species and region-specific trends. Using a combination of meta-regression and generalized linear models, we found no significant temporal trend for the abundance of any species (Procambarus clarkii, Pacifastacus leniusculus or Faxonius limosus) at the European scale, but identified species-specific predictors of abundances. While analysis of the spatial range expansion of NICS was positive (i.e. increasing spread) in England and negative (significant retreat) in northern Spain, no trend was detected in Hungary and the Dutch-German-Luxembourg region. The average invasion velocity varied among countries, ranging from 30 km/year in England to 90 km/year in Hungary. The average invasion velocity gradually decreased over time in the long term, with declines being fastest in the Dutch-German-Luxembourg region, and much slower in England. Considering that NICS pose a substantial threat to aquatic biodiversity across Europe, our study highlights the utility and importance of collecting high resolution (i.e. annual) biomonitoring data using a sampling protocol that is able to estimate crayfish abundance, enabling a more profound understanding of NICS impacts on biodiversity.
Headwater streams are natural sources of methane but are suffering severe anthropogenic disturbance, particularly land use change and climate warming. The widespread intensification of agriculture since the 1940s has increased the export of fine sediments from land to streams, but systematic assessment of their effects on stream methane is lacking. Here we show that excess fine sediment delivery is widespread in UK streams ( n = 236) and, set against a pre-1940s baseline, has markedly increased streambed organic matter (23 to 100 g m −2 ), amplified streambed methane production and ultimately tripled methane emissions (0.2 to 0.7 mmol CH 4 m −2 d −1 , n = 29). While streambed methane production responds strongly to organic matter, we estimate the effect of the approximate 0.7 °C of warming since the 1940s to be comparatively modest. By separating natural from human enhanced methane emissions we highlight how catchment management targeting the delivery of excess fine sediment could mitigate stream methane emissions by some 70%.
Historical mining activities cause widespread, long-term trace metal contamination of freshwater ecosystems. However, measuring trace metal bioavailability has proven difficult, because it depends on many factors, not least concentrations in water, sediment and habitat. Simple tools are needed to assess bioavailabilities. The use of biomonitors has been widely advocated to provide a realistic measure. To date there have been few attempts to identify ubiquitous patterns of trace metal accumulation within and between freshwater biomonitors at geographical scales relevant to trace metal contamination. Here we address this through a nationwide collection of freshwater biomonitors (species of Gammarus, Leuctra, Baetis, Rhyacophila, Hydropsyche) from 99 English and Welsh stream sites spanning a gradient of high to low trace metal loading. The study tested for inter-biomonitor variation in trace metal body burden, and for congruence amongst accumulations of trace metals within taxa and between taxa across the gradient. In general, significant differences in trace metal body burden occurred between taxa: Gammarus sp. was the most different compared with insect biomonitors. Bivariate relationships between trace metals within biomonitors reflected trace metal profiles in the environment. Strong correlations between some trace metals suggested accumulation was also influenced by physiological pathways. Bivariate relationships between insect biomonitors for body burdens of As, Cu, Mn and Pb were highly consistent. Our data show that irrespective of taxonomic or ecological differences, there is a commonality of response amongst insect taxa, indicating one or more could provide consistent measures of trace metal bioavailability.
BACKGROUND:There is increasing recognition of adverse mental health consequences of preterm birth and the impact on social-emotional development. However, the quality of the developing parent-infant relationship may be protective, with enhanced maternal sensitivity to infants' cues associated with improved outcomes.METHODS:Eighty mothers and their preterm infants born <32 weeks gestation were randomised to intervention and standard care groups. Intervention comprised reflective interview, observation of infant cues and video interaction guidance (VIG). The primary outcome, maternal sensitivity during play, was measured by the Child Adult Relationship Evaluation-Index. Secondary outcomes were infant social-emotional problems measured by the Ages and Stages Questionnaire-Social-Emotional version.RESULTS:There was no statistically significant difference between the intervention and standard care groups in maternal sensitivity during play at 9 months corrected age (CA). In the secondary outcome analysis at 12 months CA, infants in the intervention group had fewer self-regulation problems than infants whose mothers received standard care. Per-protocol analysis revealed that infants whose mothers completed VIG had significantly fewer communication problems.CONCLUSIONS:This early attachment-focussed intervention integrating VIG for mothers and their preterm infants did not enhance maternal sensitivity; however, there were effects on infant social-emotional problems at 12 months CA.IMPACT:Preterm birth can adversely affect infant and parent mental health and the quality of the parent-infant relationship. Early intervention to support parent-infant interaction can have positive effects on infant social-emotional development. There was no statistically significant difference in maternal sensitivity during play at 9 months CA. However, there were fewer infant self-regulation and communication problems reported by mothers at 12 months CA following intervention. Further evaluations of attachment-focussed interventions in the neonatal intensive care unit are needed.
Background: MRI scoring systems are used in the perinatal period to predict later neurodevelopmental outcome in infants with neonatal encephalopathy (NE). Our objective was to compare the predictive ability of 3 MRI scoring systems for neurodevelopmental outcome at 2 years of age in infants with NE. Methods: We retrospectively analysed MRI scans from term-born neonates with NE in the first two weeks of life between February 2011 and June 2015 using three scoring systems: Barkovich, NICHD-NRN and Weeke. Neurodevelopmental outcome was assessed using Bayley Scales of Infant and Toddler Development, third edition (Bayley-III) 2 years later. After adjusting for postmenstrual age at MRI scan and therapeutic hypothermia, the relationship between scoring systems and Bayley-III composite scores was assessed by regression analysis and logistic regression was used to calculate the predictive value of MRI scoring systems for adverse outcome (Bayley-III score of <85 in any domain). Findings: Of the 136 infants recruited, MRI was performed in 99 infants. 66 infants (cooled n=49; non-cooled n=17) were assessed at two years of age, of which 16 (24%) had adverse outcomes. NICHD-NRN and Weeke scores were associated with cognitive, language and motor scores and Barkovich scores were associated with cognitive, and motor scores. In predicting adverse outcome at 2 years, sensitivity and specificity was 0.56 and 0.82 for conventional-based Barkovich, 0.56 and 0.96 for Barkovich with DWI, 0.69 and 0.80 for NICHD-NRN, and 0.50 and 0.96 for Weeke. Subcortical brain injury was highly predictive of cognitive and motor deficits, as well as adverse outcome. MRI scores in cooled infants had lower predictive ability for adverse outcome compared with non-cooled infants. Interpretation: Our results show MRI scoring systems demonstrated high specificity, however, we were not able to identify which system best predicted adverse outcome at 2 years. Therapeutic hypothermia treatment seems to reduce the predictive value of MRI scores for neurodevelopmental outcome. Funding Statement: National Children’s Research Centre, Tallaght, Ireland.Declaration of Interests: None to declare. Ethics Approval Statement: Approval was granted by the Ethics Committee of the National Maternity Hospital, Dublin, and Children’s University Hospital, Temple Street, Dublin. Written informed consent was not required in this retrospective cohort study and all patient data were processed anonymously.
Background: Magnetic resonance imaging (MRI) scoring systems are used in the neonatal period to predict outcome in infants with neonatal encephalopathy. Our aim was to assess the relationship between three MRI scores and neurodevelopmental outcome assessed using Bayley Scales of Infant and Toddler Development, third edition (Bayley-III), at two years in infants with neonatal encephalopathy. Methods: Term-born neonates with evidence of perinatal asphyxia born between 2011 and 2015 were retrospectively reviewed. MRI scanning was performed within the first two weeks of life and scored using Barkovich, National Institute of Child Health and Human Development (NICHD) Neonatal Research Network (NRN), and Weeke systems by a single assessor blinded to the infants clinical course. Neurodevelopmental outcome was assessed using composite scores on the Bayley-III at two years. Multiple linear regression analyses were used to assess the association between MRI scores and Bayley-III composite scores, with postmenstrual age at scan and sex included as covariates. Results: Of the 135 recruited infants, 90 infants underwent MRI, and of these, 66 returned for follow-up. MRI abnormalities were detected with the highest frequency using the Weeke score (Barkovich 40%, NICHD NRN 50%, Weeke 77%). The inter-rater agreement was good for the Barkovich score and excellent for NICHD NRN and Weeke scores. There was a significant association between Barkovich, NICHD NRN, and Weeke scores and Bayley-III cognitive and motor scores. Only the Weeke score was associated with Bayley-III language scores. Conclusions: Our findings confirm the predictive value of existing MRI scoring systems for cognitive and motor outcome and suggest that more detailed scoring systems have predictive value for language outcome. (c) 2021 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Neonatal encephalopathy (NE) is a significant cause of morbidity and mortality. Persistent inflammation and activation of leukocytes mediate brain injury in NE. The standard of care for NE, therapeutic hypothermia (TH), does not improve outcomes in nearly half of moderate to severe cases, resulting in the need for new adjuvant therapies, and immunomodulation holds promise. Our objective was to explore systemic leukocyte phenotype in infants with NE and healthy controls in response to lipopolysaccharide (LPS). Twenty-four infants with NE (NE II-20; NE III = 4) requiring TH and 17 term neonatal controls were enrolled, and blood samples were analyzed between days 1 and 4 of life at a mean (SD) timepoint of 2.1 (± 0.81) days of postnatal life at the time of the routine phlebotomy. Leukocyte cell surface expression levels of Toll-like receptor 4, NADPH oxidase (NOX2), CD11b, mitochondrial mass, and mitochondrial superoxide production were measured by flow cytometry. Gene expression of TRIF (TIR domain–containing adapter-inducing interferon-β), MyD88 and IRAK4 was measured by reverse transcription–polymerase chain reaction. Infants with NE had significantly lower expression of neutrophil CD11b and NOX2 with LPS stimulation compared to healthy term controls. Mitochondrial mass in neutrophils and monocytes was significantly increased in NE infants with LPS compared to controls, potentially indicating a dysregulated metabolism. Infants with NE had significantly lower IRAK4 at baseline than controls. NE infants display a dysregulated inflammatory response compared to healthy infants, with LPS hyporesponsiveness to CD11b and NOX2 and decreased IRAK4 gene expression. This dysregulated immune profile may indicate an adaptable response to limit hyperinflammation.
Aim: To investigate the relationship between cytokines associated with innate immune cell activation and brain injury and outcome in infants with NE compared to neonatal controls. Methods: Serum and CSF biomarkers associated with activated neutrophils and monocytes [Interleukin-8 (IL-8) and Granulocyte-Macrophage-Colony-Stimulating-Factor (GM-CSF)] were serially measured using duplex immunoassays on days 1, 3 and 7 in term newborns with NE and controls. Results were compared to grade of encephalopathy, seizures, MRI brain imaging, mortality and Bayley Score of Infant and Toddler Development (Bayley-III) at 2 years of age. Results: Ninety-four infants had serum samples collected with 34 CSF samples. NE Grade II/III was significantly associated with elevated on day 2 serum IL-8. Mortality was best predicted by elevated day 1 IL-8. GM-CSF was initially elevated on day 1 and abnormal MRI imaging was associated with decreased day 2 GM-CSF. Elevated GM-CSF at day of life 6–7 correlated negatively with composite cognitive, language and motor Bayley-III scores at 2 years. Conclusion: Moderate or severe NE and mortality was associated with elevated IL-8. Day 2 GM-CSF could predict abnormal MRI results in NE and Bayley-III. Therefore, these cytokines are altered in NE and may predict early outcomes and further implicate inflammatory processes in NE.