Integrating research on bacterial pathogens and commensals to fight infections-an ecological perspective

Ultrasound-activated sonothermal-catalytic synergistic therapy via asymmetric electron distribution for bacterial wound infections

Antibiotic-resistant bacterial infections present a growing global health challenge, requiring innovative therapeutic solutions to overcome current limitations. We introduce boron-integrated bismuth oxide (B-BiO2) nanosheets with an asymmetrically distributed electronic structure for ultrasound-activated synergistic sonothermal and catalytic therapy. Boron incorporation enhances local electron density distribution, optimizing charge separation and significantly improving sonothermal and catalytic efficiency, as validated by density functional theory calculations. These nanosheets exhibit dual functionality, effectively generating localized heat and reactive oxygen species (ROS) under ultrasound, leading to 99.999 % antibacterial efficacy against multidrug-resistant pathogens by disrupting bacterial membranes, as demonstrated through all-atom simulations and in vitro experiments. The simulations further reveal that sonothermal conversion effects enhance bacterial membrane fluidity and induce structural defects, amplifying ROS-induced oxidative damage and membrane destabilization. In vivo, B-BiO2 nanosheets accelerate wound healing in methicillin-resistant Staphylococcus aureus (MRSA)-infected murine models, achieving 99.8 % closure by day 14 by reducing inflammation and promoting angiogenesis and tissue regeneration. Transcriptomic analysis highlights the activation of extracellular matrix remodeling, angiogenesis, and autophagy pathways, underscoring the nanosheets' therapeutic potential. This study establishes ultrasound-activated B-BiO2 nanosheets as a novel nanotherapeutic platform, leveraging asymmetric electron distribution to synergistically combat drug-resistant infections and promote effective wound healing.

Akkermansia muciniphila enhances mucosal immunity against porphyromonas gingivalis

OBJECTIVE

This study aims to investigate the immunomodulatory potential of Akkermansia muciniphila in restoring Porphyromonas gingivalis-induced immune dysfunction.

DESIGN

The immune response was assessed by measuring the expression of pro-inflammatory cytokines and antibacterial peptides in human gingival epithelial cells and human gingival fibroblasts treated with A. muciniphila, P. gingivalis, or a combination of both. Activation of the NF-κB pathway was analyzed using immunofluorescent staining and western blot. In vivo validation was performed using a mouse model, where A. muciniphila and P. gingivalis were administered alongside a MyD88-specific inhibitor to confirm the immunomodulatory mechanisms.

RESULTS

A. muciniphila significantly enhanced the defensive immune response through TLR-MYD88-NF-κB pathway. In vitro and in vivo, A. muciniphila upregulated chemokine expression to recruit immune cells. A. muciniphila also reduced the adhesion and internalization of P. gingivalis and increased the expression of genes encoding antimicrobial peptides (DEFB103B and CAMP).

CONCLUSIONS

A. muciniphila demonstrates potential in combating P. gingivalis infection highlighting its role as a promising immune modulator for periodontal disease management.

Travel to the tropics: Impact on gut microbiota

BACKGROUND

Visitors to low- and middle-income countries (LMICs) encounter numerous new intestinal microbes, including diarrhoeal pathogens and multidrug-resistant (MDR) bacteria, such as extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE). Consequently, many develop travellers' diarrhoea (TD) and/or become colonised by ESBL-PE. We explored the impact of LMIC travel, TD, and ESBL-PE/diarrheal pathogen colonisation on gut microbiota.

METHODS

The present study included 92 participants from the clinical vaccine trial OEV123, who spent 12 days in Benin, West Africa, and provided exploratory pre- and post-travel stool microbiota samples. The samples were subjected to quantitative polymerase chain reaction (qPCR) to detect diarrhoeal pathogens and 16S rRNA gene amplicon sequencing for microbiota profiling.

RESULTS

Travel significantly altered gut microbiota, showing reduced richness, decreased α-diversity, and a 40-fold increase in Escherichia/Shigella. qPCR detected diarrhoeagenic Escherichia coli (DEC) in post-travel stools of 89 % of the 92 participants. No specific microbiota signatures were linked to TD or ESBL-PE acquisition. Participants acquiring multiple DEC pathotypes had higher pre-travel levels of Ruminococcaceae and Coprococcus spp., while their post-travel microbiota was enriched with oxygen-tolerant and oral and upper gastrointestinal tract-associated taxa.

CONCLUSION

Travel to an LMIC significantly impacted intestinal microbiota. Individuals with high pre-travel proportions of Ruminococcaceae and Coprococcus spp. acquired a greater DEC pathotype diversity. However, no specific pre-travel microbiota profile was identified as protective against or predisposing to TD or acquisition of MDR bacteria.

Prescribing sustainability: should UN sustainable development goals be part of the medical, pharmacy, and biomedical education?

Introduction

How to adapt the curriculum of medicine, pharmacy, and biomedical sciences to prepare future health professionals to meet the challenge of maintaining quality care in a period of socio-ecological crisis? Addressing connections between humanity and sustainable environment should include an analysis of the reciprocal influence of various ecosystems, since it is now clear that healthcare systems have an impact on ecosystems and vice versa. Here, we propose that integrating the United Nations Sustainable Development Goals (SDGs) into the curriculum could be a first step in such a transversal education.

Methods

Members of the faculty of medicine at the University of Namur, Belgium, including teaching staff of the department of medicine, pharmacy, biomedical sciences and psychology, were invited to respond anonymously to a questionnaire about their views on the feasibility of integrating the SDGs into their teaching. A subsequent survey on students' perceptions of such teaching was conducted by student representatives.

Results

Seventy-nine percent of surveyed members of the medical faculty believe that it is possible to integrate SDGs into their lectures. However, 44-86% of them did not know how to integrate each individual goal. 94.4% of students would like SDGs to play a greater role in their education; 64.4% of them would integrate them into existing modules; 23.9% would create an optional module, and 11.9% would create a mandatory module.

Conclusion

Sustainable Development Goals integration into the curriculum of medicine, pharmacy, and biomedical sciences is perceived as challenging in a dense teaching program. To clarify how SDGs can translate into traditional lectures, we provide for each SDG targeted applications for bachelor's, master's and continuing education.

Deciphering internal and external factors influencing intestinal junctional complexes

The intestinal barrier, an indispensable guardian of gastrointestinal health, mediates the intricate exchange between internal and external environments. Anchored by evolutionarily conserved junctional complexes, this barrier meticulously regulates paracellular permeability in essentially all living organisms. Disruptions in intestinal junctional complexes, prevalent in inflammatory bowel diseases and irritable bowel syndrome, compromise barrier integrity and often lead to the notorious "leaky gut" syndrome. Critical to the maintenance of the intestinal barrier is a finely orchestrated network of intrinsic and extrinsic factors that modulate the expression, composition, and functionality of junctional complexes. This review navigates through the composition of key junctional complex components and the common methods used to assess intestinal permeability. It also explores the critical intracellular signaling pathways that modulate these junctional components. Lastly, we delve into the complex dynamics between the junctional complexes, microbial communities, and environmental chemicals in shaping the intestinal barrier function. Comprehending this intricate interplay holds paramount importance in unraveling the pathophysiology of gastrointestinal disorders. Furthermore, it lays the foundation for the development of precise therapeutic interventions targeting barrier dysfunction.