BMC Ecology and Evolution - Boosting tree growth in the Amazon rainforest using Amazonian Dark Earths

Restoring degraded tropical ecosystems is a major ecological challenge, particularly in vast, nutrient‑poor regions of the Amazon. Amazonian Dark Earths (ADE), known for their exceptional fertility and resilience, have been proposed as a sustainable strategy to support forest recovery. This study investigates whether ADE can enhance the growth of key Amazonian tree species by reshaping soil microbial communities.

Researchers applied small amounts of ADE to soils supporting two tree species, Schizolobium amazonicum and Handroanthus avellanedae. They measured growth indicators such as plant height and stem diameter and analyzed microbiome shifts. ADE significantly improved growth in both species and fundamentally reorganized the soil microbiome. It reduced opportunistic and pathogenic microbes, including Lasiodiplodia and Pseudoxanthomonas, while increasing beneficial biocontrol and growth‑promoting taxa such as Metarhizium, Tomentella, Rhizobium, and Enterobacter.

The findings show that ADE acts as a powerful suppressive soil that restructures microbial communities, enhancing plant health and accelerating forest restoration. Its value lies not only in its nutrient richness but in its ability to create a beneficial microbial environment, offering a scalable, sustainable solution for restoring degraded Amazonian landscapes.

BMC Nutrition - Efficacy of an intervention in the nutritional status and consumption of ultra-processed foods in children with obesity treated in primary health care in Brazil

Childhood obesity is a growing public health challenge, and effective management requires comprehensive, family‑ and community‑engaged approaches within primary health care. Ultra‑processed food consumption plays a major role in excess weight gain. This study evaluates whether a structured behavioral and nutritional intervention can improve dietary habits and nutritional status among Brazilian children with obesity.

A randomized clinical trial was conducted across 20 primary health care units in Betim, Brazil, involving children aged 6-10 years with obesity. Participants were allocated to an intervention group receiving monthly activities and weekly sessions totaling ≥26 contact hours, or a control group receiving up to 9 hours of counseling. Among 167 randomized children, the intervention significantly reduced ultra‑processed food consumption at multiple follow‑up visits, although no significant changes were observed in BMI or BMI‑for‑age z‑scores.

The intervention effectively reduced ultra‑processed food consumption intake and supported weight maintenance, indicating its potential as a primary health care strategy for managing childhood obesity. Although BMI did not decrease, sustained improvements in eating behaviors highlight the value of integrating structured nutritional programs into routine primary care.

BMC Health Services Research - Healthcare professionals’ views on barriers, facilitators and optimisation of care for perinatal anxiety: a qualitative investigation

Around one in five women experience perinatal anxiety during pregnancy and the postpartum period, which can have a negative impact on the well-being of mothers, infants, and families. Therefore, strengthening early identification and management is essential. Despite ongoing investment in specialist perinatal mental health pathways, little is known about how healthcare professionals experience these systems, particularly when supporting women with mild to moderate mental health needs.

This qualitative study interviewed 62 healthcare professionals from England and Scotland working in maternity services, primary care, health visiting and specialist mental health services. Using framework analysis, the study examined the barriers and facilitators to identification, disclosure, referral, assessment, and treatment. 40% of participants had received no formal perinatal mental health training, and 45% did not use standardized screening tools, revealing notable inconsistencies.

The findings show that, while pathways for severe perinatal mental health issues are well established, support for mild to moderate anxiety remains limited. Participants emphasized the need for accredited, accessible and well-funded training, as well as long-term investment to ensure a sufficient and well-distributed workforce capable of supporting women experiencing perinatal anxiety.

BMC Public Health - Outdoor night light exposure and sleep structure, a panel study using consumer-grade wearables

Urbanization has greatly increased outdoor nighttime light levels, leaving homes and workplaces constantly illuminated and reducing true darkness. Such exposure can potentially disrupt circadian rhythms and affect sleep quality, making it important to understand how nighttime light influences different stages of sleep.

This study explored the association between nighttime light exposure and sleep structure in a large Chinese population. Sleep data from 4,690 participants wearing consumer‑grade tracking devices between 2017 and 2019 were analyzed. Outdoor nighttime light exposure was estimated using NASA’s Black Marble dataset and was assessed through mixed‑effects regression models adjusted for demographic, behavioral, and environmental factors. Higher nighttime light exposure was associated with a small increase in light sleep duration. These effects are most significant among older adults with lower BMI. Restricted cubic spline analyses suggested a modest decline at higher nighttime light levels.

Overall, the findings indicate that moderate nighttime light may slightly extend light sleep, whereas higher exposure could reduce deep sleep. These insights highlight the need for urban lighting policies that protect both safety and sleep health, while supporting further research on personalized light exposure and indoor environmental factors.

BMC Infectious Diseases - Nucleocapsid protein enhances spike- and RBD-specific humoral and cellular immune responses in protein-based SARS-CoV-2 vaccine

Current COVID‑19 vaccines effectively prevent severe disease but offer limited protection against infection and transmission, especially as new variants emerge. Broader and longer‑lasting immunity may require vaccines that generate strong systemic and mucosal antibody responses as well as robust T‑cell activation. This study examines whether including the SARS‑CoV‑2 nucleocapsid (N) protein alongside spike (S) or receptor‑binding domain (RBD) antigens can enhance immune responses in protein-based vaccine candidates.

Mice received three immunizations with various antigen combinations containing Fc‑fused RBD, S, and/or N proteins. Vaccines were administered intranasally, subcutaneously, or with intramuscular priming followed by intranasal boosting, using BPEI or AS04 as adjuvants. Fc‑fused RBD induced stronger antibody responses than full‑length S. Importantly, adding small amounts of N protein boosted both systemic and mucosal IgG/IgA responses and significantly enhanced IL‑2 and IFN‑γ secretion by splenocytes. Intramuscular priming followed by intranasal boosting produced the most consistent neutralizing antibody and T‑cell responses.

The study demonstrates that incorporating nucleocapsid protein strengthens both humoral and cellular immunity in protein‑based SARS‑CoV‑2 vaccines. These findings highlight the potential of multicomponent vaccine designs and support further development of strategies that elicit complementary systemic and mucosal protection.