Plasma ammonia concentrations in extremely low birthweight infants in the first week after birth: secondary analysis from the ProVIDe randomized clinical trial.

BACKGROUND: Little is known about normative ammonia concentrations in extremely low birthweight (ELBW) babies and whether these vary with birth characteristics. We aimed to determine ammonia concentrations in ELBW babies in the first week after birth and relationships with neonatal characteristics and protein intake. METHODS: Arterial blood samples for the measurement of plasma ammonia concentration were collected within 7 days of birth from ProVIDe trial participants in six New Zealand neonatal intensive care units. RESULTS: Three hundred and twenty-two babies were included. Median (range) gestational age was 25.7 (22.7-31.6) weeks. Median (interquartile range (IQR)) ammonia concentration was 102 (80-131) µg/dL. There were no statistically significant associations between ammonia concentrations and birthweight or sex. Ammonia concentrations were weakly correlated with mean total (Spearman's rs = 0.11, P = 0.047) and intravenous (rs = 0.13, P = 0.02) protein intake from birth, gestational age at birth (rs = -0.13, P = 0.02) and postnatal age (rs = -0.13, P = 0.02). CONCLUSIONS: Plasma ammonia concentrations in ELBW babies are similar to those of larger and more mature babies and only weakly correlated with protein intake. Currently, recommended thresholds for investigation of hyperammonaemia are appropriate for ELBW babies. Protein intake should not be limited by concerns about potential hyperammonaemia.

Is Lactoferrin More Effective in Reducing Late-Onset Sepsis in Preterm Neonates Fed Formula Than in Those Receiving Mother's Own Milk? Secondary Analyses of Two Multicenter Randomized Controlled Trials.

BACKGROUND: Lactoferrin is the major antimicrobial protein in human milk. In our randomized controlled trial (RCT) of bovine lactoferrin (BLF) supplementation in preterm neonates, BLF reduced late-onset sepsis (LOS). Mother's own milk (MM) contains higher concentrations of lactoferrin than donor milk or formula, but whether BLF is more effective in infants who receive formula or donor milk is uncertain. AIM: To evaluate the incidence of LOS in preterm infants fed MM and in those fed formula and/or donor milk. STUDY DESIGN: This is a (A) post hoc subgroup analysis, in our RCT of BLF, of its effects in preterm infants fed MM, with or without formula, versus those fed formula and/or donor milk (no-MM) and (B) post hoc meta-analysis, in our RCT of BLF and in the ELFIN (Enteral Lactoferrin in Neonates) RCT, of the effect of BLF in subgroups not exclusively fed MM. RESULTS: (A) Of 472 infants in our RCT, 168 were randomized to placebo and 304 were randomized to BLF. Among MM infants, LOS occurred in 22/133 (16.5%) infants randomized to placebo and in 14/250 (5.6%) randomized to BLF (relative risk or risk ratio (RR): 0.34; relative risk reduction (RRR): 0.66; 95% confidence interval (95% CI) for RR: 0.18-0.64; p < 0.0008). Among no-MM infants, LOS occurred in 7/35 (20.0%) randomized to placebo and in 2/54 (3.7%) randomized to BLF (RR: 0.19; RRR: 0.81; 95% CI for RR: 0.16-0.96; p = 0.026). In multivariable logistic regression analysis, there was no interaction between BLF treatment effect and type of feeding (p = 0.628). (B) In 1,891 infants not exclusively fed MM in our RCT of BLF and in the ELFIN RCT, BLF reduced the RR of LOS by 18% (RR: 0.82; 95% CI: 0.71-0.96; p = 0.01). CONCLUSION: Adequately powered studies should address the hypothesis that BLF is more effective in infants fed formula or donor milk than those fed MM. Such studies should evaluate whether a specific threshold of total lactoferrin intake can be identified to protect such patients from LOS.

Extensive marine anoxia during the terminal Ediacaran Period.

The terminal Ediacaran Period witnessed the decline of the Ediacara biota (which may have included many stem-group animals). To test whether oceanic anoxia might have played a role in this evolutionary event, we measured U isotope compositions (δ238U) in sedimentary carbonates from the Dengying Formation of South China to obtain new constraints on the extent of global redox change during the terminal Ediacaran. We found the most negative carbonate δ238U values yet reported (-0.95 per mil), which were reproduced in two widely spaced coeval sections spanning the terminal Ediacaran Period (551 to 541 million years ago). Mass balance modeling indicates an episode of extensive oceanic anoxia, during which anoxia covered >21% of the seafloor and most U entering the oceans was removed into sediments below anoxic waters. The results suggest that an expansion of oceanic anoxia and temporal-spatial redox heterogeneity, independent of other environmental and ecological factors, may have contributed to the decline of the Ediacara biota and may have also stimulated animal motility.

Community-Academic Partnership: Establishing the Institute for Mental Health Research Early Psychosis Intervention Center.

Growing evidence suggests that specialized, multicomponent intervention provided early in the course of a psychotic disorder may have a positive effect in ameliorating the morbidity and mortality associated with these disorders. This column describes the development of the Institute for Mental Health Research Early Psychosis Intervention Center, which leverages the unique strengths of a community and academic partnership to provide such specialty care in a youth-friendly, stigma-free environment. Since it opened in 2016, the program has had numerous successes, including securing increased reimbursements rates and performance-based incentives for the treatment of first-episode psychosis.

Managing conflicts between economic activities and threatened migratory marine species toward creating a multiobjective blue economy.

Harnessing the economic potential of the oceans is key to combating poverty, enhancing food security, and strengthening economies. But the concomitant risk of intensified resource extraction to migratory species is worrying given these species contribute to important ecological processes, often underpin alternative livelihoods, and are mostly already threatened. We thus sought to quantify the potential conflict between key economic activities (5 fisheries and hydrocarbon exploitation) and sea turtle migration corridors in a region with rapid economic development: southern and eastern Africa. We satellite tracked the movement of 20 loggerhead (Caretta caretta) and 14 leatherback (Dermochelys coriacea) turtles during their postnesting migrations. We used movement-based kernel density estimation to identify migration corridors for each species. We overlaid these corridors on maps of the distribution and intensity of economic activities, quantified the extent of overlap and threat posed by each activity on each species, and compared the effects of activities. These results were compared with annual bycatch rates in the respective fisheries. Both species' 3 corridors overlapped most with longline fishing, but the effect was worse for leatherbacks: their bycatch rates of approximately 1500/year were substantial relative to the regional population size of <100 nesting females/annum. This bycatch rate is likely slowing population growth. Artisanal fisheries may be of greater concern for loggerheads than for leatherbacks, but the population appears to be withstanding the high bycatch rates because it is increasing exponentially. The hydrocarbon industry currently has a moderately low impact on both species, but mining in key areas (e.g., Southern Mozambique) may undermine >50 years of conservation, potentially affecting >80% of loggerheads, 33% of the (critically endangered) leatherbacks, and their nesting beaches. We support establishing blue economies (i.e., generating wealth from the ocean), but oceans need to be carefully zoned and responsibly managed in both space and time to achieve economic (resource extraction), ecological (conservation, maintenance of processes), and social (maintenance of alternative livelihood opportunities, alleviate poverty) objectives.

Population structure of humpback whales from their breeding grounds in the South Atlantic and Indian Oceans.

Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527 samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence, the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed fidelity of migratory destinations, along with other ecological and oceanographic features in the region.