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The breakdown of allochthonous organic matter is considered to be the main source of energy and nutrients for the majority of first-order streams. Thus, land-use change and riparian vegetation, such as deforestation and conversion of native forest to pasture lands, will lead to unwanted changes of the structure and function of aquatic ecosystems due to the disturbance of organic-matter supply. The C4 grasses, extensively used as forage in tropical regions, are poorly studied as important sources of allochthonous material because they are usually considered as a poor source of nutrients. Because the effects of land-use change on ecosystem functions are not fully known, we aimed to evaluate how such changes in riparian vegetation can affect nutrient cycling by means of measuring the decomposition rate of an abundant native C3 species and an exotic C4 grass species in first-order streams of the Atlantic Forest. Our results showed that C4 detritus decomposed faster than did C3 detritus, despite its lower nutrient concentration. This was likely to be due to the lower lignin concentration of the C4 species than the native C3 species. Lignin also influenced nutrient-loss dynamics of the C3 species, because it can interact with other cellular constituents and prevent the decomposition of most labile compounds. Our results supported the observation that the replacement of riparian vegetation alters breakdown rates and nutrient distributions, which may disrupt aquatic food webs. [ABSTRACT FROM AUTHOR]

We studied 91 offspring of ABO incompatible preganacies and 30 controls resulting from O--O pregnancies to test whether cord bilirubin levels could be used to predict the severity of hyperbilirubinaemia in ABO incompatibility. Blood group, direct Coombs's test, and serum bilirubin estimations were carried out on cord blood, and bilirubin estimations at 12, 24, 36, and 48 hours of life. [ABSTRACT FROM AUTHOR]

Objective: Determine the sensitivity and specificity of neonatal jaundice visual estimation by primary healthcare workers (PHWs) and physicians as predictors of hyperbilirubinaemia., Design: Multicentre observational cohort study., Setting: Hospitals in Chandigarh and Delhi, India; Dhaka, Bangladesh; Durban, South Africa; Kumasi, Ghana; La Paz, Bolivia., Participants: Neonates aged 1-20 days (n=2642) who presented to hospitals for evaluation of acute illness. Infants referred for any reason from another health facility or those needing immediate cardiopulmonary resuscitation were excluded., Outcome Measures: Infants were evaluated for distribution (head, trunk, distal extremities) and degree (mild, moderate, severe) of jaundice by PHWs and physicians. Serum bilirubin level was determined for infants with jaundice, and analyses of sensitivity and specificity of visual estimations of jaundice used bilirubin thresholds of >260 µmol/L (need for phototherapy) and >340 µmol/L (need for emergency intervention in at-risk and preterm babies)., Results: 1241 (47.0%) neonates had jaundice. High sensitivity for detecting neonates with serum bilirubin >340 µmol/L was found for 'any jaundice of the distal extremities (palms or soles) OR deep jaundice of the trunk or head' for both PHWs (89%-100%) and physicians (81%-100%) across study sites; specificity was more variable. 'Any jaundice of the distal extremities' identified by PHWs and physicians had sensitivity of 71%-100% and specificity of 55%-95%, excluding La Paz. For the bilirubin threshold >260 µmol/L, 'any jaundice of the distal extremities OR deep jaundice of the trunk or head' had the highest sensitivity across sites (PHWs: 58%-93%, physicians: 55%-98%)., Conclusions: In settings where serum bilirubin cannot be measured, neonates with any jaundice on the distal extremities should be referred to a hospital for evaluation and management, where delays in serum bilirubin measurement and appropriate treatment are anticipated following referral, the higher sensitivity sign, any jaundice on the distal extremities or deep jaundice of the trunk or head, may be preferred., Competing Interests: Competing interests: RB and MW are WHO staff members. MW contributed to study design, implementation, data analysis and manuscript writing and RB contributed to data analysis and manuscript writing. The opinions expressed in this paper do not necessarily represent the position of the WHO. The funding agencies did not influence the conduct or outcomes of the study, data analysis or interpretation, or preparation of this paper. The authors declare no other potential competing interests., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.)

Nhecolândia is a vast sub-region of the Pantanal wetland in Brazil with great diversity in surface water chemistry evolving in a sodic alkaline pathway under the influence of evaporation. In this region, >15,000 shallow lakes are likely to contribute an enormous quantity of greenhouse gas to the atmosphere, but the diversity of the biogeochemical scenarios and their variability in time and space is a major challenge to estimate the regional contribution. From 4 selected alkaline lakes, we compiled measurements of the physico-chemical characteristics of water and sediments, gas fluxes in floating chambers, and sedimentation rates to illustrate this diversity. Although these lakes have a similar chemical composition, the results confirm a difference between the black-water and green-water alkaline lakes, corresponding to distinct biogeochemical functioning. This difference does not appear to affect lake sedimentation rates, but is reflected in gas emissions. Black-water lakes are CO 2 and CH 4 sources, with fairly constant emissions throughout the seasons. Annual carbon dioxide and methane emissions approach 0.86molm -2 y -1 and 0.07molm -2 y -1 , respectively, and no clear trend towards N 2 O capture or emission was observed. By contrast, green-water lakes are CO 2 and N 2 O sinks but important CH 4 sources with fluxes varying significantly throughout the seasons, depending on the magnitude of the phytoplankton bloom. The results highlight important daily and seasonal variations in gas fluxes, and in particular a hot moments for methane emissions, when the O 2 -supersaturation is reached during the afternoon under extreme bloom and sunny weather conditions, provoking an abrupt O 2 purging of the lakes. Taking into account the seasonal variability, annual methane emissions are around 10.2molm -2 y -1 , i.e., much higher than reported in previous studies for alkaline lakes in Nhecolândia. Carbon dioxide and nitrous oxide consumption is estimated about 1.9molm -2 y -1 and 0.73mmolm -2 y -1 , respectively. However, these balances must be better constrained with systematic and targeted measurements throughout the seasons., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Neonatal illness is a leading cause of death worldwide; sepsis is one of the main contributors. The etiologies of community-acquired neonatal bacteremia in developing countries have not been well characterized., Methods: Infants <2 months of age brought with illness to selected health facilities in Bangladesh, Bolivia, Ghana, India, Pakistan and South Africa were evaluated, and blood cultures taken if they were considered ill enough to be admitted to hospital. Organisms were isolated using standard culture techniques., Results: Eight thousand eight hundred and eighty-nine infants were recruited, including 3177 0-6 days of age and 5712 7-59 days of age; 10.7% (947/8889) had a blood culture performed. Of those requiring hospital management, 782 (54%) had blood cultures performed. Probable or definite pathogens were identified in 10.6% including 10.4% of newborns 0-6 days of age (44/424) and 10.9% of infants 7-59 days of age (39/358). Staphylococcus aureus was the most commonly isolated species (36/83, 43.4%) followed by various species of Gram-negative bacilli (39/83, 46.9%; Acinetobacter spp., Escherichia coli and Klebsiella spp. were the most common organisms). Resistance to second and third generation cephalosporins was present in more than half of isolates and 44% of the Gram-negative isolates were gentamicin-resistant. Mortality rates were similar in hospitalized infants with positive (5/71, 7.0%) and negative blood cultures (42/557, 7.5%)., Conclusions: This large study of young infants aged 0-59 days demonstrated a broad array of Gram-positive and Gram-negative pathogens responsible for community-acquired bacteremia and substantial levels of antimicrobial resistance. The role of S. aureus as a pathogen is unclear and merits further investigation.

Identification of simple signs and symptoms that predict severe illness needing referral for admission of young infants is critical for reducing mortality in developing countries. Infants <2 months of age presenting to two hospitals in La Paz, Bolivia (n=1082) were evaluated by nurses for signs and symptoms, and independently by physicians for the need for admission. In young neonates, sensitivity of individual clinical signs was >35% for measured temperature ≥ 37.5° C (65%); all signs had specificity >85%. Odds ratios (ORs) for association of individual clinical signs with need for urgent hospital management were highest (>5) for history of difficulty feeding, not feeding well and fever. Clinical signs or symptoms are useful for primary healthcare workers to identify young infants with serious illness needing admission, and have been incorporated into the Integrated Management of Childhood Illness algorithm for use in Bolivia and elsewhere in Latin America.

Objective: To determine the clinical and epidemiological features of infants with extreme hyperbilirubinemia who require exchange transfusion (ET)., Study Design: Term and near-term infants admitted to a paediatric hospital over a 5-year period in La Paz, Bolivia, were included in the study if they met the following criteria: age less than 30 days; total serum bilirubin (TSB) levels > or =428 micromol/L (> or =25 mg/dL) on admission and if they had undergone an ET., Results: Fifty-six infants were identified during the study period. Most of them were exclusively breastfed (98.2%). Median age at admission was 7 days. Weight loss of more than 12% since birth, as well as dehydration, was registered in more than one-third of cases. Extreme hyperbilirubinemia was considered as secondary to increased enterohepatic circulation (EHC) in most cases (73%). The mean TSB level on admission was 531.8 micromol/L (31.1 mg/dL). Fifteen infants (26.8%) showed signs of acute bilirubin encephalopathy (ABE). Early ABE was reversible after ET in most cases but all infants with advanced ABE developed severe kernicteric sequelae. Nine patients (16.1%) developed adverse events attributable to ET., Conclusions: Dehydration and weight loss in breastfed infants appeared to be an important factor associated with extreme hyperbilirubinemia and secondary brain damage during the first week of life. This may well be avoided if signs of ABE and its associated conditions are identified appropriately by follow-up programmes.

Radiography plays an important role in a neonatal intensive care nursery. Diagnostic radiation was measured in 96 newborns. Mean exposure per neonate was 68.1 milliroentgens (mR) (SD = 132.7) with a median exposure per neonate of 28 mR. Radiation received by neonates was low, but further studies are needed to show the safety of radiation or its delayed effects. The measurement of radiation is simple, and routine radiation recording can prove useful in future evaluations of this high-risk population.

Out of 262 premature newborn patients admitted with a diagnosis of respiratory distress, it was necessary to treat 70 with a ventilator. Of these 70, 25 eventually underwent tracheostomy. Indications for tracheostomy were that of an infant needing prolonged endotracheal intubation greater than one week. The procedure itself was easily performed and an overall complication rate of 7% was the result. Of the patients who underwent tracheostomy, 8% had significant complications. There was no death attributable to the treatment regime. We feel, therefore, that a combination approach starting with the endotracheal tube and progressing to tracheostomy when necessary, provided the best care for premature infants requiring intensive airway management.