Frontiers in Microbiology最新文献

Background: Commercial foot-and-mouth disease (FMD) vaccines have several drawbacks, including a short duration of the immune response after vaccination and local adverse reactions at the vaccination site. Therefore, we developed a new vaccination strategy that simultaneously improves the health status of the host and stimulates systemic immunity by combining the oral administration of glycyrrhizic acid (GA) and intramuscular injection of the FMD vaccine.

Methods: We evaluated the efficacy of the oral immune enhancer GA in conjunction with an intramuscular injection of the FMD vaccine. After vaccination, the experimental (mice) and target animals (pigs) were orally administered GA daily for 4 weeks and once a week for the next 4 weeks. Subsequently, we evaluated safety using various biochemical serum assays, the efficacy of inducing immune responses using serological assays, and the expression of genes related to systemic immunity induction.

Results: Oral administration of GA in combination with an intramuscular injection of the FMD vaccine enhanced early, mid-term, and long-term immunity in experimental and target animals. We also confirmed that this co-administration increased the expression of secretory IgA (sIgA), an important indicator of mucosal immunity. Additionally, significant gene elevations in systemic immune markers along with T helper (Th) immune responses were observed.

Conclusion: These findings suggest that combining the oral administration of GA with the intramuscular injection of an inactivated FMD vaccine can induce a potent and sustained immune response and stimulate the systemic immune system by promoting sIgA and cytokine gene expression. Our research can be used to enhance the efficacy of existing commercial vaccines as well as control other animal diseases by improving the host's immune system.

Objective: With the growing emphasis on global health issues, Brucellar spondylitis, a serious complication of brucellosis, has received increasing attention from researchers. This study employed bibliometric analysis to visually illustrate the scientific advancements and research trends in the field of Brucellar spondylitis research, providing a scientific basis for public health prevention and control strategies.

Method: The data were sourced from the Web of Science Core Collection database, covering the period from January 1, 1984, to December 31, 2023. Network analyses of countries, institutions, authors, and keyword collaborations, as well as co-citation analyses of journals and references, were conducted using CiteSpace software. VOSviewer software was used to analyze the co-occurrence and hotspots of keywords.

Result: A total of 246 relevant documents were retrieved, comprising 221 articles and 25 review articles. From 1984 to 2023, the number of research publications exhibited a generally fluctuating upward trend. Turkey and China emerged as the primary contributing countries in this field, with Xinjiang Medical University identified as the most productive research institution. Additionally, Juan D. Colmenero is recognized as the author with the highest number of published articles and citations. "Clinical Infectious Diseases" is regarded as the most influential journal in this domain. Among the 404 keywords analyzed by CiteSpace, the top 10 high-frequency keywords included spondylitis, complication, melitensis, osteoarticular complication, diagnosis, infection, clinical characteristics, epidural abscess, arthritis, and feature. A total of 14 clusters were formed. In the burst analysis of the top 15 keywords, "instrumentation" exhibited the highest burst intensity, while "arthritis" demonstrated the longest burst duration. Emerging keywords include "experience," "ankylosing spondylitis," "China," and "instrumentation."

Conclusion: This study is the first bibliometric analysis in the field of Brucellar spondylitis, which revealed that the research hotspots in this field included the clinical characteristics of the disease, the management of complications, and treatment strategies. The development trend may involve enhancements in early diagnostic methods and advancements in surgical instruments. This study serves as a valuable reference for future research directions.

Introduction: Hematogenous infections caused by Bordetella pertussis are rare. This study aimed to increase clinicians' knowledge of B. pertussis bacteremia.

Methods: We described a case of an infant with B. pertussis bacteremia, searched and reviewed for B. pertussis bacteremia-related literatures published in the PubMed database between 1946 to 2022.

Results: A 3-month-old male infant was admitted to the hospital with a respiratory tract infection. Respiratory pathogen testing indicated the presence of B. pertussis, cytomegalovirus, and respiratory syncytial viruses. Blood metagenomic next-generation sequencing (mNGS) confirmed B. pertussis bacteremia. After 32 days of anti-infective treatment and supportive therapy, the patient's condition improved, and he was discharged. The literature review found that B. pertussis bacteremia is rare, often with fever as the first symptom, and is most common in individuals with underlying diseases or prolonged immunosuppressive therapy.

Discussion: In infants lacking specific protective antibodies against B. pertussis, B. pertussis bacteremia should be considered when bacteremia-associated clinical manifestations are present and the causative organism remains undetected. Timely refinement of mNGS can help clarify the diagnosis.

Introduction: Bamboo is a sustainable and degradable resource for sustenance, high-strength cellulose microfibers, and synthetic fiber in China. Endophytic bacteria enhance root development and ethylene levels, benefiting the host plants' physiology.

Methods: We investigated the population, diversity, and abundance of endophytic bacteria in the leaves of three bamboo species-Phyllostachys edulis, Bambusa rigida, and Pleioblastus amarus-using high-throughput 16S rDNA sequencing.

Results and discussion: A total of 1,159 operational taxonomic units (OTUs) were obtained and further classified into 26 phyla, 64 classes, 158 orders, 270 families, 521 genera, and 811 species. The phyla with the highest abundance were Proteobacteria, Actinobacteria, and Myxococcota, and the highest genera included 1,174-901-12, Sphingomonas, and unclassified_f__Enterobacteriaceae. The relative richness of endophytic bacteria in the three species was in the following order: B. rigida > P. amarus > Ph. edulis. The PICRUSt functional richness analysis of endophytic bacteria indicated their involvement in six biological pathways: "cellular processes," "environmental information processing," "genetic information processing," "human diseases," "metabolism," and "organic systems." Among the 41 sub-functions, the most common were "amino acid metabolism," "carbohydrate metabolism," "cell motility," "cellular signaling," "energy metabolism," and "membrane transport." Our results provide precise knowledge for better managing bamboo forests and pave the way for isolating secondary metabolites and potential bioactive compounds.

Uranium mining presents significant environmental challenges, particularly through radiological contamination affecting soil and water bodies. While soil microbial communities are known to be influenced by geochemical factors like pH and nutrient availability, their responses to severe uranium contamination in mine tailing environments remain poorly understood. This study investigated microbial community distributions in soils and uranium ores at four uranium mining sites in South China to explore microbial adaptations to uranium contamination. Uranium concentrations ranged from 170 to 18,000 mg/kg, with the most severely contaminated samples dominated by Cyanobacteria, which comprised up to 49.17% of the microbial community. Proteobacteria, such as Sphingomonas, were also abundant, indicating their roles in radiation resistance, while Acidobacteriota and Actinobacteria showed negative responses to uranium. Addition of lime to neutralize the acidity in mine tailings led to an increase in Gemmatimonadaceae, a family commonly found under oligotrophic conditions. Multivariate statistical analyses confirmed uranium concentration as the primary factor influencing microbial composition, along with pH values, total nitrogen, and contents of Fe₂O₃ and SiO₂ in soils. Co-occurrence network analysis suggested that extremely high uranium concentrations disrupted microbial interrelationships, reflecting communities lived more independently and adopted strategies to cope with the intense selective pressure. Intriguingly, dispersal limitation governed 90% of community assembly in high-uranium environments (>10,000 mg/kg), suggesting more isolated ecological niches. Deterministic processes such as heterogeneous and homogeneous selection only dominated the community assembly at relatively moderate to low uranium levels. These findings provide insights into the ecological dynamics of uranium-contaminated sites and related bioremediation strategies.

[This corrects the article DOI: 10.3389/fmicb.2024.1448675.].

Herpes simplex virus type I (HSV-1) infection-induced host transcript ion shutdown is one of the most critical hallmarks of viral lytic infection. However, how HSV-1 and which viral factors accomplish this dramatic effect is not well understood. In this study, we show that ICP22-defined condensates shutdown host global transcription but facilitate viral transcription. This is independent of its effects on viral infection-triggered changes in splicing, readthrough, and read-in events. ICP22 condensates depleted the serine-2 phosphorylated RNA polymerase II (RNAPII Ser-2P) occupancy from the host transcription start site (TSS), resulting in decreased host transcripts output. At the same time, it ensures proper RNAPII Ser-2P distribution on the viral genome to promote viral transcription. This effect is dependent solely on the condensate-forming activity, as condensate-disrupting point mutations abolish it. In addition, ectopic expressed ICP22 alone could decrease host transcription activity and increase histone H3K27me3 modification level. Thus, ICP22 condensates shut down host transcription by reducing RNAPII binding to host TSS to impair the host transcription.

The non-structural protein 4 (NSP4) of porcine reproductive and respiratory syndrome virus (PRRSV) is equipped with 3C-like serine protease (3CLSP) activity, influencing crucial aspects such as virus replication, host IFN-β suppression, host cell apoptosis induction, and PRRSV detection facilitation. In response to wild or attenuated PRRSV strains, antibodies against non-structural proteins are generated, while inactivated vaccines fail to elicit such responses. Employing the Enzyme-Linked Immunosorbent Assay (ELISA) method targeting non-structural proteins helps discern the immune effects of inactivated versus wild or attenuated vaccine strains. The study focused on the NSP4 protein from the PRRSV XH-GD strain (GenBank No. EU624117.1), which was cloned, expressed, and leveraged as a coating protein for establishing an indirect enzyme-linked immunosorbent assay (ELISA) detection method. This method showcased outstanding specificity, repeatability, and sensitivity, exhibiting a notable agreement rate of 91.74% with the PRRSV IDEXX ELISA kit. The successful development of the NSP4 indirect ELISA not only supports the detection of PRRSV antibodies but also provides a robust platform for ongoing antibody monitoring in pig farming. Utilizing PRRSV NSP4 for ELISA antibody detection offers a more sustainable approach for continuous surveillance. The high agreement between this method and commercial kits lays a solid groundwork for effectively differentiating between inactivated and attenuated vaccines, enhancing the management and monitoring of PRRSV in pig populations.