Search Results (7,063)

Continuous planting results in a higher occurrence rate of oriental melon Fusarium wilt caused by Fusarium oxysporum f. sp. melonis (FOM), and treatment with Trichoderma can considerably alleviate the incidence of disease. However, the tripartite interaction mechanisms among T. harzianum–melon–rhizosphere microorganisms remain poorly understood in current research. Pot experiments elucidate the growth-promoting, antagonistic, and rhizosphere-regulating effects of T. harzianum on oriental melon. The experiment consisted of two treatments: (1) water control (CK), and (2) T. harzianum inoculation (MM) with three repetitions per treatment. Illumina high-throughput sequencing was employed to analyze the microbial community and associated metabolic pathways. Additionally, a comprehensive correlation analysis clarified how T. harzianum-modulated physiological factors regulate soil microbial communities to enhance melon resistance to FOM. T. harzianum inoculation significantly promoted plant growth, decreased the incidence rate of Fusarium wilt by 41.85%, and increased rhizosphere nitrate-N, pH, EC, and soil enzyme activity (e.g., sucrose and alkaline phosphatase). Notably, T. harzianum inoculation altered the rhizosphere microbial community’s relative abundance and structure, with the most striking changes in the fungal community. Principal coordinate analysis showed this fungal restructuring accounted for 44.9% of total community variation (37% from PCo1, 7.9% from PCo2). Soil-borne pathogens (e.g., Fusarium, Verticillium, Phytophthora) decreased in relative abundance with the inoculation of T. harzianum. Meanwhile, the microbial community shifted from a “fungal-dominated” to “bacterial-dominated” state: fungal proportion decreased by 9.47% (from 23.95% in CK to 14.48% in MM), while bacterial proportion increased by 9.47% (from 76.05% in CK to 85.52% in MM). Microbial abundance shifts primarily impacted amino acid and cofactor biosynthesis metabolic pathways. The application of T. harzianum modified the soil environment, restructuring microbial communities through these changes, which in turn regulated microbial metabolic pathways, creating a soil environment conducive to melon growth and thereby enhancing oriental melon resistance to FOM, while mitigating the obstacles of continuous cropping. Full article

Background and Clinical Significance: Anaerococcus tetradius (A. tetradius) and Gardnerella vaginalis (G. vaginalis) are rare etiological factors for postpartum endometritis and are typically associated with bacterial vaginosis. However, in some cases, G. vaginalis and A. tetradius can cause serious postpartum endometritis with complications such as sepsis. Case Presentation: 26-year-old pregnant woman expecting monochorionic diamniotic twins presented to the hospital at 35 weeks and 3 days of gestation and two male infants were delivered via the Cesarean section. On the fifth day after delivery, the patient began to complain of intense abdominal pain, a fever of 37.9 °C, and overall weakness. Blood tests revealed neutrophilic leukocytosis, increased C-reactive protein (CRP) of 225.4 mg/L. Upon examination, abdominal distension, tenderness on palpation, and positive symptoms of peritoneal irritation were present and the site of the abdominal incision was inflamed with flowing foul-smelling greenish pus. Ultrasound examination revealed free fluid collection in the peritoneal cavity, under the liver, and around the uterus. Later, the condition of the patient worsened with progressing and respiratory distress. As a result, suppurative peritonitis and sepsis was suspected and the patient underwent urgent total hysterectomy without oophorectomy. Acute endometritis, focal myometritis, and chronic cervicitis were concluded from histopathological examination of the removed uterus. Microbiological tests showed the most abundant growth of A. tetradius in the wound cultures and great abundance of G. vaginalis in the abdominal cavity cultures. After trying three different treatment schemes and difficulties with determining the antibiotic sensitivity tests for pathogens, the antibacterial therapy was escalated to Meropenem, which was found to be effective, and the patient was discharged home. Conclusions: This case report highlights the severity of complications of postpartum endometritis that can be caused by rare pathogens (such as G. vaginalis and A. tetradius), and strategies for how to manage it. The clinical presentation of a patient should be monitored closely for several days after Cesarean section and if endometritis is suspected, microbiological cultures are necessary to determine the cause of infection and implement an appropriate treatment. Full article

Background: Occlusion of plastic biliary stents is a common complication in biliary drainage, often requiring exchange procedures every 2–4 months due to microbial colonization and sludge formation. This study aimed to evaluate diamond-like carbon (DLC) coatings, with and without silver nanoparticle additives, for preventing stent occlusion. Methods: Polyethylene (PE) stents were coated with DLC using PlasmaImpax for DLC-1 and pulsed laser deposition for DLC-2. Silver ions (Ag) were incorporated into the DLC-2 coatings. To simulate in vivo conditions, a co-culture of Enterococcus faecalis (E. faecalis), Escherichia coli (E. coli), and Candida albicans (C. albicans) was used for microbial colonization. Standardized human bile simulated physiological conditions. Adhesion tests, weight measurements, and scanning electron microscopy (SEM) quantified bacterial adherence to stents. Results: DLC-1 coatings demonstrated higher bacterial growth than uncoated PE stents with E. faecalis (adhesion assay difference: 0.6 log [p = 0.19] and 0.1 log [p = 0.75] in rounds 1 and 2, respectively). In the bile incubation model, DLC-1 did not significantly reduce bacterial counts at 5 days (0.4 log [p = 0.06]) or 14 days (0.2 log [p = 0.44]). DLC-2 showed no significant reduction either. DLC-2-Ag significantly reduced bacterial adhesion (5 days: −0.3 log [p = 0.00]; 14 days: −0.4 log [p = 0.16]) and exhibited inhibition zones against E. faecalis (2.3 mm), E. coli (2.1 mm), and C. albicans (0.6 mm). SEM revealed cracks and flaking in the coating. Conclusions: DLC coatings alone did not prevent microbial adhesion. Tendencies of anti-adhesive properties were seen with Ag-doped DLC coatings, which were attributed to the antibacterial effects of Ag. Optimization of the DLC-coating process is needed to improve stent performance. Future studies with larger samples sizes are needed to confirm the observed trends. Full article

Background/Objectives: The Type IV pilus assembly system in Acinetobacter baumannii is a major determinant of its pathogenicity, playing a role in surface-associated functions via the biogenesis of Type IV pili (T4P). Tazobactam (TAZ) is a well-characterized β-lactamase inhibitor, primarily used in combination with β-lactam antibiotics such as piperacillin (PIP) to counteract bacterial resistance mechanisms. While A. baumannii resistance to β-lactam antibiotics has been well studied, the influence of T4P on its susceptibility to TAZ remains largely unexplored. For this reason, we investigated how multidrug-resistant A. baumannii 5075 (AB5075) responds to TAZ by assessing the roles of pilA, pilB, and pilD in bacterial growth and biofilm formation under direct TAZ exposure, with a focus on phenotypic characterization rather than molecular mechanisms. Methods: Bacterial growth kinetics were quantified by measuring the optical densities of cell suspensions and the colony forming units per volume (CFUs/mL) at different time intervals. Time-kill assays and microtiter dish biofilm formation assays were used to evaluate how effectively TAZ can inhibit growth and biofilm formation, respectively. Results: Time–kill assays confirmed that 32 µg/mL of TAZ inhibited growth in both wild-type (WT) and mutant strains, with the pilD mutant showing initial resistance before eventual inhibition. Biofilm assays showed that the pilA mutant had the highest biofilm formation at 8 h, surpassing the WT strain. A prolonged 32 µg/mL of TAZ exposure (24–36 h) significantly reduced biofilm production across all strains, with inhibition rates reaching 89% for the WT, 82% for the pilA mutant, 91% for the pilB mutant, and 86% for the pilD mutant. Conclusion: These findings deepen our understanding of the strain-specific roles of T4P components in growth and biofilm regulation in AB5075, and highlight the potential of TAZ as a therapeutic strategy against biofilm-associated infections. Full article

This study investigated the effects of Clostridium butyricum (C. butyricum) supplementation on the bacterial community composition and fermentation characteristics of the digestive system, assessed blood antioxidant capacity, and evaluated growth performance and digestibility in pre-weaning Angus calves. Sixteen male Angus calves were randomly divided into two groups (n = 8). The control group was fed a basal diet, while the other group was supplemented with 2 × 10⁷ colony-forming unit/d C. butyricum in the basal diet. After 8 weeks of feeding, body growth and nutrient intake were measured. Rumen fluid samples, blood samples, and fecal samples were collected and analyzed. Fecal scores were recorded daily, and the frequency of diarrhea treatments was documented. The results showed C. butyricum supplementation improved the digestibility of neutral detergent fiber, crude protein, and ether extract in calves, as well as the growth hormone content in the blood. Furthermore, supplementation elevated isovaleric acid concentrations in the rumen, modulated the microbiome, and increased pre-weaning body weight and average daily gain of calves. Meanwhile, C. butyricum supplementation reduced myeloperoxidase and superoxide dismutase levels while increasing total antioxidant capacity in the blood, alleviating oxidative stress, and enhancing the antioxidant capacity of the body. Intestinal health was also improved, as evidenced by an increase in butyrate content, a reduction in enterotoxigenic Escherichia coli, lower fecal scores, and a decreased need for diarrhea treatments. In summary, dietary C. butyricum supplementation may support digestive system development, enhance antioxidant capacity, and improve growth performance and health status in pre-weaning Angus calves. Full article

Obesity is a growing global health challenge, closely linked to chronic low-grade inflammation. This persistent, low-intensity immune response contributes to the development of metabolic, cardiovascular, and cancer-related diseases. A key player in this process is the gut microbiota. Dysbiosis, an imbalance in gut bacterial composition, disrupts metabolic function, weakens the intestinal barrier, and promotes the production of pro-inflammatory cytokines. In people with obesity, gut microbial diversity is reduced, and the ratio of beneficial to harmful bacteria shifts, affecting lipid metabolism and immune balance. Short-chain fatty acids, produced by gut bacteria, help maintain gut integrity and reduce inflammation. Butyrate, a major SCFA, also improves insulin sensitivity and may support obesity treatment. Diet plays a central role in shaping the gut microbiome. Western diets tend to promote dysbiosis and inflammation, while Mediterranean-style diets encourage the growth of beneficial bacteria. Targeted modulation of the microbiota through diet, probiotics, or medication emerges as a promising strategy for preventing and managing obesity. Full article

The taxonomic status of two bacterial strains, KW56^T and 2063^T, isolated from root nodules of Chamaecytisus albus (Spanish broom), was investigated using a polyphasic approach. Both isolates belong to the genus Phyllobacterium, yet exhibit significant genotypic and phenotypic differences from all currently described species. Whole-genome comparisons revealed that strain KW56^T is most closely related to Phyllobacterium trifolii PETP 02^T, while strain 2063^T is related to Phyllobacterium brassicacearum strains STM 196^T and 29-15. However, digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values between the new isolates and their closest relatives were below established species delineation thresholds, supporting their recognition as novel species. Phenotypic analyses confirmed morphological and growth characteristics typical for Phyllobacterium, while also revealing several discriminatory physiological traits. Fatty acid profiling showed that cyclopropyl 19:0 was the major fatty acid in both strains, though each exhibited a unique fatty acid composition. Chemotaxonomic markers included 3-OH 14:0, a19:1, and 21:0 for strain KW56^T, and 3-OH 14:0, 3-OH 17:0, and 3-OH 18:0 for strain 2063^T. Based on the genomic, phenotypic, and chemotaxonomic data, we propose that strains KW56^T and 2063^T represent two novel species, for which the names Phyllobacterium chamaecytisi sp. nov. (DSM 113831) and Phyllobacterium lublinensis sp. nov. (DSM 113830) are proposed. Full article

The effects of Phellodendron chinense plantations on soil properties, microbial characteristics, and the plant diversity across forest age remain poorly understood. In this study, four forest ages (2-, 5-, 8-, and 12-year-old) were examined to compare soil nutrient status, rhizosphere microbial community composition, and plant diversity. Our results showed that understory vegetation comprised 56 plant species from 29 families, with species richness significantly increasing with forest age. Rhizosphere soils showed a marked decline in pH and a significant increase in organic carbon, while nutrient dynamics followed distinct trends: P and Mg exhibited continuous accumulation; N displayed unimodal patterns; and K and Ca initially decreased before rising. Microbial community structure shifted significantly with forest age—the dominant bacterial phylum transitioned from Proteobacteria in young stands to Acidobacteriota in mature forests, whereas fungal communities underwent a successional sequence from Basidiomycota (2a) to Ascomycota (5–8a) and finally to Rozellomycota (12a). Correlation analyses demonstrated that plant diversity (S index) was positively correlated with P, K, Ca, and Mg, whereas fungal Shannon diversity was primarily driven by soil N and pH. These findings indicate that forest age mediates plant–soil-microbe interactions through rhizosphere environmental changes. For sustainable plantation management, we recommend (1) dynamically optimizing understory vegetation composition, (2) regulating soil pH and moisture during key growth stages, and (3) selecting compatible companion plants to enhance rhizosphere conditions. Full article

Background/Objectives: The consumption of liquid egg products is rising. While thermal pasteurization improves safety and shelf life, it can affect product quality. Furthermore, egg products continue to cause many foodborne illnesses, especially those caused by Salmonella enterica subspecies enterica serovar Enteritidis (Salmonella Enteritidis). Bacteriophages (or phages) are an effective alternative to specifically fight foodborne bacteria. This study aimed to evaluate (i) the stability of phage vB_SeEM_UALMA_PCSE1 (PCSE1) under different conditions of temperature and pH; (ii) the effect of multiplicity of infection (MOI) and temperature on phage efficacy; (iii) the bactericidal effect of phage PCSE1 against S. Enteritidis in liquid whole eggs compared to thermal pasteurization; and (iv) the effect of both treatments on the physicochemical and functional properties of liquid whole eggs. Methods: For this, stability tests, bacterial growth inhibition assays in culture media and liquid eggs, and physicochemical and functional analyses were conducted. Results: Phage PCSE1 was (i) stable at pH 7 and 8, and at 4, 25, and 37 °C for 56 days; (ii) effectively prevented S. Enteritidis growth in TSB (reduction of 1.8, 4.5, and 4.5 log colony-forming units (CFU)/mL at 4, 10, and 25 °C, respectively, relative to the bacterial control); (iii) controlled S. Enteritidis in liquid whole eggs at 25 °C (reduction of 5.8 log CFU/mL relative to the bacterial control) comparable to pasteurization (reduction of 5.2 log CFU/mL); and (iv) preserved eggs’ properties, contrarily to pasteurization. Conclusions: These findings suggest PCSE1 is a promising strategy to fight S. Enteritidis in liquid egg products, though further studies on shelf-life are needed. Full article

Background: Staphylococcus aureus necrotizing fasciitis is a life-threatening infection requiring aggressive surgical and medical management. Despite these interventions, tremendous morbidity and mortality occur. Thus, novel agents are needed to reduce these negative outcomes. Consequently, the aims of this translational study were to evaluate the feasibility of using bacteriophages and the potential clinical ramifications of using bacteriophages in treatment of S. aureus necrotizing fasciitis. Methods: Necrotizing fasciitis clinical isolates (n = 6) were tested against different Staphylococcal bacteriophages (n = 4) to assess for activity. After exposure to bacteriophages that had growth inhibition for more than 16 h, the ability of S. aureus to change phenotypic expression of numerous enzymes was evaluated, and the ability to reduce bacterial virulence was measured with the Caenorhabditis elegans assay. Results: Staphylococcal myoviridae bacteriophages were able to lyse most clinical isolates (83%). Interestingly, after exposure to myoviridae bacteriophages, S. aureus isolates had no expression of hemolysin, secreted coagulase, or lecthinase, or the ability to ferment mannitol. These same bacteriophages also caused statistically significant decreases in bacterial virulence (p < 0.05). Neither findings were observed for bacteriophages of the podoviridae family. Conclusions: To use bacteriophages for S. aureus necrotizing fasciitis, cocktails of Staphylococcal myoviridae are likely needed to allow for broad host ranges, mitigating the need for in vitro sensitivity testing. Moreover, Staphylococcal myoviridae have the potential to reduce specific enzyme expression and global virulence of residual S. aureus. Thus, bacteriophages may aid in reducing necrotizing fasciitis morbidity by not only lysing S. aureus but also by reducing S. aureus virulence. Full article

The use of biomedical implants has significantly enhanced patient survival rates and overall quality of life. However, bacterial infections caused by bacterial adhesion and the subsequent formation of biofilm on the surface of the implants are challenging clinical issues, leading to implant failure and high social and economic costs. Modification of the surface of the implants with antibacterial coatings is a promising technique to address implant-associated bacterial infection problems. One strategy to fabricate bactericidal antibacterial coatings is to load antibacterial agents, like antibiotics—the most important type of antibacterial drug for killing or inhibiting the growth of bacteria—at therapeutic doses into the coatings and subsequently release them, ideally in a controlled way. Plasma electrolytic oxidation (PEO) is a simple, affordable, and eco-friendly method to produce high-performance, multifunctional coatings with desired antibacterial properties. This review examines the antibacterial activity of antibiotic-loaded PEO coatings, offering valuable insights for the development of novel, high-performance antibacterial coatings that meet clinical requirements. Full article

Background: Microbial analyses of tissue samples are of paramount importance for diagnostic and therapeutic purposes in the course of septic revision arthroplasty. Isolation and identification of the causative pathogens pave the way for successful treatment of periprosthetic joint infections, which necessitates a reliable microbiological workup. It is unknown if there are inconsistencies in pathogen detection and differentiation between accredited laboratories in the context of septic revision arthroplasty. Methods: Tissue samples of forty consecutive patients undergoing septic total hip and knee revision surgery were sent to two different accredited and certified laboratories and tested for pathogen growth and bacterial differentiation. Results: Each institution analyzed 200 specimens. Twenty-five patients (62.5%) showed consistent results between laboratories. Diverging results were observed in 15 of 40 patients (37.5%). Of these, three individuals showed pathogen growth in only one laboratory. In 12 patients with discrepant results, laboratory analyses revealed a partly different pathogen spectrum. With regard to clinical impact and infection eradication, the respective differences implicated a therapeutic response by a change of the administered postoperative antibiotic treatment in five (12.5%) of the patients. The kappa correlation coefficient indicated a slight value in terms of data consistency between institutions (k = 0.227, p = 0.151). Conclusions: The majority of evaluated samples show comparable results with regard to microbiological evaluation. Nevertheless, a substantial number of specimens were classified differently. The observed discrepancies pose a challenge for postoperative decision-making. Against this background, standardized microbiological protocols remain mandatory for a conclusive clinical implication to eradicate PJI. Full article

Maintaining teat-end integrity in dairy cows is essential to preventing intramammary infections (IMIs) in dairy cows, yet the relationship between hyperkeratosis, teat conformation, and mammary health remais underexplored. This study evaluated the relationship between teat-end hyperkeratosis, teat conformation traits, microbial colonization, and somatic cell count (SCC) in milk from 170 cows on ten commercial dairy farms in Santa Catarina, Brazil. During two farm visits, milk and teat-end swab samples from paired teats (one with hyperkeratosis, one without) were analyzed for microbial growth and SCC. SCC data were transformed into somatic cell scores (SCS). Results showed no significant association between hyperkeratosis and mastitis microorganisms, although environmental microorganisms tended to be more frequent in hyperkeratotic teats (p = 0.0778). Major microorganisms in milk were significantly associated with higher SCC (p = 0.0132). No relationship was observed between teat conformation traits and hyperkeratosis. These findings suggest that hyperkeratosis may subtly influence the teat canal to environmental bacterial colonization, underscoring the need for improved milking management practices to minimize hyperkeratosis and associated mastitis risks. Full article

In this study, a series of novel alkoxylated resorcinarenes were synthesized using secondary and tertiary alcohols under mild catalytic conditions involving iminodiacetic acid. Structural characterization, including single-crystal X-ray diffraction, confirmed the successful incorporation of branched alkyl chains and highlighted the influence of substitution patterns on molecular packing. Notably, detailed mass spectrometric analysis revealed that, under specific conditions, the reaction pathway may shift toward the formation of defined oligomeric species with supramolecular characteristics—an observation that adds a new dimension to the synthetic potential of this system. To complement the chemical analysis, selected derivatives were evaluated for biological activity, focusing on bacterial growth and biofilm formation. Using four clinically relevant strains (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis), we assessed both planktonic proliferation (OD₆₀₀) and biofilm biomass (crystal violet assay). Compound 2c (2-pentanol derivative) consistently promoted biofilm formation, particularly in S. aureus and B. subtilis, while having limited cytotoxic effects. In contrast, compound 2e and the DMSO control exhibited minimal impact on biofilm development. The results suggest that specific structural features of the alkoxy chains may modulate microbial responses, potentially via membrane stress or quorum sensing interference. This work highlights the dual relevance of alkoxylated resorcinarenes as both supramolecular building blocks and modulators of microbial behavior. Full article

Neutrophils are increasingly recognized as key players in the tumor microenvironment (TME), displaying functional plasticity that enables them to either promote or inhibit cancer progression. Depending on environmental cues, tumor-associated neutrophils (TANs) may polarize toward antitumor “N1” or protumor “N2” phenotypes, exerting diverse effects on tumor growth, metastasis, immune modulation, and treatment response. While previous studies have focused on the pathological roles of TANs in cancer, less attention has been given to how cancer therapies themselves influence the behavior of TANs. This review provides a comprehensive synthesis of current knowledge regarding the dynamics of TANs in response to major cancer treatment modalities, including chemotherapy, radiotherapy, cell-based immunotherapies, and oncolytic viral and bacterial therapies. We discuss how these therapies influence TAN recruitment, polarization, and effector functions within the TME, and highlight key molecular regulators involved. By consolidating mechanistic and translational insights, this review emphasizes the potential to therapeutically reprogram TANs to enhance treatment efficacy. A deeper understanding of context-dependent TAN roles will be essential for developing more effective, neutrophil-informed cancer therapies. Full article