The maternal microbiome is the infant’s primary microbial inheritance, transmitted mainly through the maternal gut, vaginal delivery, breast milk, and skin-to-skin contact. Maternal iron deficiency (ID), with anemia, is a common and modifiable nutritional condition associated with impaired immune function and increased preterm birth (PTB) risk, whereas evidence for ID without anemia remains limited. It may influence maternal microbial ecology; however, its potential effect on maternal-to-infant microbial transmission remains unexplored. This review, conducted across PubMed, Embase, and Web of Science (January 2000–June 2026), proposes a double-hit hypothesis defined by the source and biological context of disruption rather than by a strictly temporal sequence. The first hit comprises potentially altered maternal-origin microbial and immunologic inputs from the vaginal, gut, and breast milk ecosystems; the second hit comprises PTB and neonatal intensive care (NICU)-associated disruption of early microbial succession. Human evidence directly linking ID to vaginal dysbiosis is limited to a single study, evidence relating maternal iron status to milk lactoferrin is inconsistent, and the contribution of vaginal communities to persistent infant gut colonization remains uncertain whereas vaginal exposure may have transient ecological or immunologic effects. No study has simultaneously evaluated maternal iron biomarkers, vaginal community state type (CST), breast milk composition, maternal gut microbiome and longitudinal infant gut microbiota. The proposed framework is therefore hypothesis-generating and identifies testable pathways through which maternal ID may alter maternal microbial and immunologic inputs, while also being associated with an increased risk of PTB. PTB, together with the resulting prematurity-related vulnerability and subsequent postnatal exposures, may further disrupt early infant microbiome development.
Photodynamic therapy (PDT) has emerged as a promising non-antibiotic strategy for combating pathogenic infections through the generation of reactive oxygen species (ROS) from a light-activated photosensitizer (PS), which interrupts microbial structures and functions. Natural products such as coumarin, curcumin, riboflavin, pheophorbide a, and hypericin have long been studied as PSs that have the functions of intrinsic antimicrobial, antiviral, antifungal, and antiparasitic activities. These metabolites are broadly distributed across multiple ethnomedical traditions worldwide, with a focus on those explicitly documented in the Chinese Pharmacopoeia and widely applied in Traditional Chinese Medicine (TCM), while acknowledging their broader global distribution. Natural PSs have some limitations for PDT efficacy. Recent advances in nanotechnology and drug delivery systems have enabled the development of TCM-derived advanced PSs with improved solubility, bioavailability, and targeted accumulation at infection sites. This narrative review was conducted through a comprehensive search of multiple electronic databases, including PubMed, ScienceDirect, Scopus, Web of Science, and the China National Knowledge Infrastructure (CNKI). The search encompassed literature published over the past three decades, without restrictions on language. Studies were considered eligible if they contained the keywords “Photodynamic Therapy”, “Pathogenic infection”, “Coumarin”, “Curcumin”, “Riboflavin”, “Pheophorbide a”, and “Hypericin”. Duplicate records were excluded during screening. All relevant publications were collected, critically appraised, and synthesized to provide mechanistic insights, preclinical evidence, and translational perspectives on the application of TCM–derived PSs in photodynamic therapy against bacterial biofilms, viral pathogens, and fungal infections. The synergistic benefits include overcoming antimicrobial resistance, enhancing host immune responses, and reducing reliance on conventional antibiotics. Challenges remain in optimizing pharmacokinetics, minimizing off-target toxicity, and advancing clinical validation or translation. Thus, TCM-derived advanced PS represent a novel and integrative approach to fight against pathogenic infection, bridging ethnopharmacology with modern photomedicine, and hold significant potential or advantages for clinical application in the future.
BackgroundClear aligners create an aligner–tooth interface that may retain saliva, microorganisms, and dietary substrates. Evidence linking interface properties, oral microecological responses, and preventive interventions remains fragmented.ObjectiveTo map and synthesize evidence on clear aligner interface properties and microbial adhesion, oral microbial ecology during clear aligner wear, and strategies for biofilm control and caries-risk mitigation.MethodsFollowing Joanna Briggs Institute methodology and PRISMA-ScR guidance, PubMed, Embase, and Web of Science Core Collection were searched from inception to August 31, 2026, without language restrictions. Backward and forward citation searching supplemented database searches. Original clinical, in vitro, and ex vivo studies involving active clear aligner treatment, associated materials or interfaces, or clear-aligner-specific interventions were eligible when they reported microbial, biofilm, microbiome, metabolomic, caries-related, or mineral outcomes. Two reviewers independently screened records; two authors charted and verified data. Findings were synthesized descriptively within three evidence domains.ResultsOf 988 records, 132 reports were included. Because reports could contribute to more than one domain, 62 informed interface properties and microbial adhesion, 47 oral microbial ecology during wear, and 76 biofilm control and caries-risk mitigation. No single polymer, manufacturing method, or surface parameter consistently predicted microbial adhesion or biofilm formation. Outcomes reflected interactions among material characteristics, local topography, salivary conditioning, aging and exposure, microbial species, and experimental models. Clinical microbial responses were compartment- and time-dependent. Salivary and tooth-associated communities often remained relatively stable at the community level, whereas the inner aligner surface sometimes exhibited localized taxonomic, functional, metabolic, and pH-related changes. Investigated interventions included cleaning, antimicrobial and antifouling interface modifications, anticaries and remineralizing approaches, probiotics, and environment-responsive systems. Although many strategies reduced microbial burden, biofilm-related outcomes, acidogenicity, or mineral loss under tested conditions, evidence was predominantly short-term and preclinical. Assessments of durability, material performance, and safety were heterogeneous.ConclusionsClear aligner–microbiota interactions appear context-dependent rather than uniformly favorable or unfavorable. Evidence neither establishes causal relationships between interface or microecological changes and clinical disease nor identifies a universally superior intervention. More standardized, clinically representative evidence may clarify their clinical relevance and inform preventive management during clear aligner treatment.
Helicobacter pylori (H. pylori) infection is associated with colorectal neoplasia in many observational studies, but a causal relationship and a preventive effect of eradication remain unestablished. This narrative review integrates clinical, microbial, experimental, and treatment evidence using four questions: which infection phenotype was measured, whether exposure preceded the colorectal outcome, whether a proposed intermediate was experimentally perturbed, and whether a defined intervention changed that outcome. Positive observational syntheses contrast with weaker or inconsistent prospective serological and genetic findings. Residual confounding, including socioeconomic and lifestyle differences, and non-equivalent exposure measurements limit causal interpretation. Gastric atrophy, endocrine changes, microbial remodeling, metabolites, and immune responses provide candidate links, but no complete infection-to-neoplasia sequence has been demonstrated in humans. Microbiota-dependent tumor promotion in genetically susceptible mice provides experimental support within that setting, whereas reduced tumor formation in an inflammation-driven model limits generalization. Neither model reproduces the duration and heterogeneity of human infection. Eradication findings depend on comparator selection, sufficient latency, and separation of randomized treatment assignment from successful clearance. A comparative appraisal links each proposed mechanism to its strongest available evidence, unresolved human causal link, and required validation. Infection status alone is not established as a basis for changing colorectal screening or claiming colorectal cancer prevention through eradication. Longitudinal human sampling, targeted tests of candidate intermediates, and long-term intervention analyses with explicit treatment comparisons are needed to establish clinical relevance.
Salmonella enterica (S. enterica) is a major foodborne pathogen that threatens human health. Multidrug resistance (MDR) has complicated the prevention and treatment of salmonellosis. The present study aimed to characterize the antimicrobial resistance patterns, population structure, and genomic features of clinical S. enterica isolates from Guangdong, China. Among 4413 isolates collected between 2022 and 2024, 1084 underwent antimicrobial susceptibility testing and 170 were further analyzed by whole-genome sequencing. MDR was defined as resistance to at least three antimicrobial classes and was identified in 71.13% of the tested isolates. Genomic analyses included serotyping, multilocus sequence typing, resistance and virulence gene analyses, and core-genome phylogenetic analysis. XGBoost and LASSO were used to prioritize genomic features associated with MDR phenotype. Serovar I 4,[5],12:i:- was the predominant serovar among MDR isolates, while ST34 and ST19 were the most common sequence types. Compared with non-MDR isolates, MDR isolates more frequently carried several resistance genes, including CTX-M-55, qnrS1, tet(A), floR, sul2, sul3, and TEM-1. Differences in virulence gene content were also observed between the two groups. Both XGBoost and LASSO consistently prioritized floR and CTX-M-55 as candidate genomic features associated with the MDR phenotype. Overall, MDR and non-MDR clinical S. enterica isolates from Guangdong differed markedly in lineage distribution and gene carriage, providing a genomic basis for regional surveillance of MDR S. enterica.
