Search Results (41,745)

Methicillin-resistant Staphylococcus aureus (MRSA) is a highly threatening foodborne pathogen capable of causing severe organ and life-threatening diseases. Over the past years, various commercial antibiotics have been used to treat MRSA infections. However, these commercial antibiotics have not yielded efficient results and also cause other side effects; therefore, there is a need for the development of effective alternatives to replace these commercial antibiotics. Suberanilic acid, an amide alkaloid obtained from the endophytic fungus Pestalotiopsis trachycarpicola DCL44, has been identified as a significant antimicrobial agent. However, its antibiotic properties on multi-drug-resistant bacteria such as MRSA have not been fully explored. Therefore, to investigate the potential antimicrobial mechanism of suberanilic acid against MRSA, a quantitative proteomics approach using tandem mass tagging (TMT) was used. The results obtained in the study revealed that suberanilic acid targets multiple pathways in MRSA, including disruption of ribosome synthesis, inhibition of membrane translocation for nutrient uptake (ABC transporter system), and causing dysregulation of carbohydrate and amino acid energy metabolism. These results provide new insights into the mechanism of action of suberanilic acid against MRSA and offer technical support and a theoretical basis for the development of novel food antimicrobial agents derived from endophytic fungal origin. Full article

The monitoring of stranded marine mammals represents a strategic method to assess their health, conservation status, and ecological role in the marine ecosystem. Networks worldwide track stranding events for the passive monitoring of mortality patterns, emerging and reemerging pathogens, climate change, and environmental degradation from a One Health perspective. This study summarizes pathogen prevalence data from the Italian Stranding Network (ISN) derived from post-mortem investigations on cetaceans found dead stranded along the Italian coastline between 2015 and 2020. The decomposition of the carcasses and logistics limited the post-mortem examination to 585 individuals, out of 1236 single-stranding reports. The most relevant pathogens identified were Cetacean Morbillivirus, Herpesvirus, Brucella spp., and Toxoplasma gondii, whose roles as environmental stressors are well known, despite their real impact still needing to be investigated in depth. Statistical analysis showed that age and sex seem to be positively related to the presence of pathogens. This study represents the first step in harmonizing post-mortem investigations, which is crucial for evidence-based conservation efforts. Implementing diagnostic and forensic frameworks could offer an indirect insight into the systematic monitoring of diseases to improve the identification of regional and temporal hotspots in which to target specific mitigation, management, and conservation strategies. Full article

Despite the impact of mastitis on sheep production worldwide, the pathogenesis and host response to bacterial infection of the ovine mammary gland are poorly characterized. Studies in cattle highlight the significance of the mammary epithelium in pathogen recognition and the subsequent host response. The objective of this study was to assess bacterial adherence, invasion, and Toll like receptor (TLR) gene expression in primary sheep mammary epithelial cells (pMEC) following co-culture with the three principal mastitis pathogens of sheep, Mannheimia haemolytica, Staphylococcus aureus, and Streptococcus uberis. S. aureus was 140-fold more adherent than S. uberis and 850-fold more adherent than M. haemolytica. However, only S. aureus was internalized after 3 hours of co-culture. TLR1, 2, 3, 4, 6, and 9 were shown to be constitutively transcribed by pMEC. M. haemolytica induced upregulation of transcription of TLR1, 2, 3, and 4. By contrast, S. uberis and S. aureus induced concentration-dependent transcription of TLR2 and TLR4 with a higher level of transcription in cells stimulated with the bacteria at a multiplicity of infection (MOI) of 200 compared to cells stimulated with a MOI of 20. These experiments define the range of TLR genes constitutively transcribed in sheep pMEC and show that bacterial infection has the capacity to regulate transcription in a species-specific and concentration-dependent manner. Full article

The petal blight disease of alpine Rhododendron severely impacts the ornamental and economic values of Rhododendron. Plant secondary metabolites play a crucial role in resisting pathogenic fungi, yet research on metabolites in alpine Rhododendron petals that confer resistance to pathogenic fungi is limited. In the present study, the secondary metabolites in Rhododendron delavayi, R. agastum, and R. irroratum petals with anti-pathogenic activity were screened through disease index analysis, metabolomic detection, the mycelial growth rate, and metabolite spraying experiments. Disease index analysis revealed that R. delavayi petals exhibited the strongest disease resistance, while R. agastum showed the weakest, both under natural and experimental conditions. UHPLC-QTOF-MS/MS analysis identified 355 and 274 putative metabolites in positive and negative ion modes, respectively. The further antifungal analysis of differentially accumulated baicalein, diosmetin, and naringenin showed their half-inhibitory concentrations (IC50) against Neopestalotiopsis clavispora to be 5000 mg/L, 5000 mg/L, and 1000 mg/L, respectively. Spraying exogenous baicalein, diosmetin, and naringenin significantly alleviated petal blight disease caused by N. clavispora infection in alpine Rhododendron petals, with the inhibition rates exceeding 64%. This study suggests that the screened baicalein, diosmetin, and naringenin, particularly naringenin, can be recommended as inhibitory agents for preventing and controlling petal blight disease in alpine Rhododendron. Full article

Several studies have demonstrated that ultraviolet-band-C (UV-C) irradiation can enhance plants’ natural resistance to pathogens and diseases. A suitable dose of UV-C radiation induces the production of metabolites that strengthen plant defenses, an effect known as “hormesis”. Hormesis presents a promising alternative that could supplement and reduce the use of pesticides, which pose risks to the environment and human health. This paper investigates the effects of UV-C radiation emitted by an array of Light-Emitting Diodes (LEDs) in generating a hormetic response in three kiwifruit species, namely A. chinensis var. deliciosa cv. Hayward, A. chinensis var. chinensis cv. Soreli^®, and A. arguta plantlets, grown in vitro and in pots, exposed to the pathogen Pseudomonas syringae pv. actinidiae (Psa) either before or after UV-C irradiation. Analyses of morpho-physiological parameters and spectrophotometric assays were conducted to evaluate changes in chlorophyll a and b content, carotenoids, total phenols, and antioxidant activity in relation to the UV-C irradiation. Results indicate partial protection against Psa infection and increased levels of chlorophylls, carotenoids, polyphenols and antioxidant activity. The optimal UV-C dose was determined to be 2.2 kJ/m² for in vitro shoots and 1.3 kJ/m², for ex vitro plants. Full article

Plant pathogens are an important agricultural problem, and early and rapid pathogen identification is critical for crop preservation. This work focuses on using fluorescence spectroscopy to characterize and compare healthy and fungal pathogen-infected wheat grains. The excitation–emission matrices of whole wheat grains were measured using a fluorescence spectrometer. The samples included healthy control samples and grains manually infected with Fusarium graminearum and Alternaria alternata fungi. The five distinct zones were identified by analyzing the location of the fluorescence peaks at each measurement. The zone centered at λ_em = 328/λ_ex= 278 nm showed an increase in intensity for grains infected with both pathogens during all periods of the experiment. Another zone with the center λ_em = 480/λ_ex = 400 nm is most interesting from the point of view of early diagnosis of pathogen development. A statistically significant increase of fluorescence for samples with F. graminearum is observed on day 1 after infection; for A. alternata, on day 2, and the fluorescence of both decreases to the control level on day 7. Moreover, shifts in the emission peaks from 444 nm to 452 nm were recorded as early as 2–3 h after infection. These results highlight fluorescence spectroscopy as a promising technique for the early diagnosis of fungal diseases in cereal crops. Full article

Inflammatory bowel disease (IBD) is an incurable, chronic disorder of the gastrointestinal tract whose incidence increases every year. Scientific research constantly delivers new information about the disease and its multivariate, complex etiology. Nevertheless, full discovery and understanding of the complete mechanism of IBD pathogenesis still pose a significant challenge to today’s science. Recent studies have unanimously confirmed the association of gut microbial dysbiosis with IBD and its contribution to the regulation of the inflammatory process. It transpires that the altered composition of pathogenic and commensal bacteria is not only characteristic of disturbed intestinal homeostasis in IBD, but also of viruses, parasites, and fungi, which are active in the intestine. The crucial function of the microbial metabolome in the human body is altered, which causes a wide range of effects on the host, thus providing a basis for the disease. On the other hand, human genomic and functional research has revealed more loci that play an essential role in gut homeostasis regulation, the immune response, and intestinal epithelial function. This review aims to organize and summarize the currently available knowledge concerning the role and interaction of crucial factors associated with IBD pathogenesis, notably, host genetic composition, intestinal microbiota and metabolome, and immune regulation. Full article

Few therapeutic options are available to treat COVID-19. The KEAP1/NRF2 pathway, the major redox-responsive pathway, has emerged as a potential therapeutic target for COVID-19 as it regulates redox homeostasis and inflammation that are altered during SARS-CoV-2 infection. Here, we characterized the effects of NRF2-agonist Sulfodyne^®, a stabilized natural Sulforaphane, in cellular and animal models of SARS-CoV-2 infection. In pulmonary or colonic epithelial cell lines, Sulfodyne^® elicited a more efficient inhibition of SARS-CoV-2 replication than NRF2-agonists DMF and CDDO. This antiviral activity was not dependent on NRF2 but was associated with the regulation of several metabolic pathways, including the inhibition of ER stress and mTOR signaling, which are activated during SARS-CoV-2 infection. Sulfodyne^® also decreased SARS-CoV-2 mediated inflammatory responses by inhibiting the delayed induction of IFNB1 and type I IFN-stimulated genes in infected epithelial cell lines and by reducing the activation of human by-stander monocytes recruited after SARS-CoV-2 infection. In K18-hACE2 mice infected with SARS-CoV-2, Sulfodyne^® treatment reduced both early lung viral load and disease severity by fine-tuning IFN-beta levels. Altogether, these results provide evidence for multiple mechanisms that underlie the antiviral and anti-inflammatory activities of Sulfodyne^® and pinpoint Sulfodyne^® as a potent therapeutic agent against pathogenic effects of SARS-CoV-2 infection. Full article

Codonopsis pilosula is an important medicinal plant in China. Continuous cropping of C. pilosula affects crop quality and yield. However, comprehensive research on the impacts of continuous cropping on soil properties, microbial community structures, and soil metabolites is lacking. This study involved collecting rhizosphere soil samples from C. pilosula monocropped for 1 to 4 years to analyze variations in soil properties, microbial community structure, and metabolites across different continuous-cropping years (CCYs) through metabolomic and microbiomic analyses. Significant variations in the soil properties were observed; total phosphorus (TP) and available potassium (AK) in the rhizosphere soil increased with the number of CCYs, and pH declined. The microbial community structure significantly changed with continuous cropping. Overall, the soil bacterial diversity decreased with increasing CCY. The abundances of Proteobacteria and Firmicutes significantly decreased with increasing CCY, whereas the abundance of Acidobacteria significantly increased. The fungal diversity tended to decrease, with an increase in the abundance of beneficial Basidiomycota and an increase in potentially pathogenic Rozellomycota. Metabolomic analysis revealed 101 metabolites and significant changes in lipid compounds, organic acids, phenols, and carbohydrates. Notably, autotoxic substances such as 2,6-di-tert-butylphenol accumulated with increasing CCY. The results indicated that the main factors causing continuous-cropping obstacles in C. pilosula were soil nutrient imbalance and autotoxic substance accumulation. Continuous cropping of C. pilosula significantly altered the microbial community structure and metabolomic profile of rhizosphere soils. Effective management practices are needed to mitigate soil acidification, nutrient imbalances, and autotoxic substance accumulation during continuous cropping. Future research should focus on integrated soil management strategies to maintain soil health and crop productivity in C. pilosula continuous-cropping systems. Full article

Marburg hemorrhagic fever (MHF) is a fatal infectious disease caused by Marburg virus (MARV) infection, and MARV has been identified as a priority pathogen for vaccine development by the WHO. The glycoprotein (GP) of MARV mediates viral adhesion and invasion of host cells and therefore can be used as an effective target for vaccine development. Moreover, DNA vaccines have unique advantages, such as simple construction processes, low production costs, and few adverse reactions, but their immunogenicity may decrease due to the poor absorption rate of plasmids. Lysosome-associated membrane protein 1 (LAMP1) can direct antigens to lysosomes and endosomes and has great potential for improving the immunogenicity of nucleic acid vaccines. Therefore, we constructed a DNA vaccine based on a codon-optimized MARV GP (ID MF939097.1) fused with LAMP1 and explored the effect of a LAMP targeting strategy on improving the immunogenicity of the MARV DNA vaccine. ELISA, ELISpot, and flow cytometry revealed that the introduction of LAMP1 into the MARV DNA candidate vaccine improved the humoral and cellular immune response, enhanced the secretion of cytokines, and established long-term immune protection. Transcriptome analysis revealed that the LAMP targeting strategy significantly enriched antigen processing and presentation-related pathways, especially the MHC class II-related pathway, in the candidate vaccine. Our study broadens the strategic vision for enhanced DNA vaccine design and provides a promising candidate vaccine for MHF prevention. Full article

Staphylococcus pseudintermedius is frequently associated with several bacterial infections in dogs, highlighting a One Health concern due to the zoonotic potential. Given the clinical significance of this pathogen, we performed comprehensive genomic analyses of 28 S. pseudintermedius strains isolated from canine infections throughout whole-genome sequencing using Illumina HiSeq, and compared the genetic features between S. pseudintermedius methicillin-resistant (MRSP) and methicillin-susceptible (MSSP) strains. Our analyses determined that MRSP genomes are larger than MSSP strains, with significant changes in antimicrobial resistance genes and virulent markers, suggesting differences in the pathogenicity of MRSP and MSSP strains. In addition, the pangenome analysis of S. pseudintermedius from canine and human origins identified core and accessory genomes with 1847 and 3037 genes, respectively, which indicates that most of the S. pseudintermedius genome is highly variable. Furthermore, phylogenomic analysis clearly separated MRSP from MSSP strains, despite their infection sites, showing phylogenetic differences according to methicillin susceptibility. Altogether our findings underscore the importance of studying the evolutionary dynamics of S. pseudintermedius, which is crucial for the development of effective prevention and control strategies of resistant S. pseudintermedius infections. Full article

To manage the number of critical COVID-19 patients, Umberto I Teaching Hospital in Rome established a temporary ICU on March 1, 2021. This study investigated the incidence and risk factors of healthcare-associated infections (HAIs) among these patients during various COVID-19 waves. Patients were grouped by admission date according to the dominant SARS-CoV-2 variant prevalent at the time (Alpha, Delta, Omicron BA.1, Omicron BA.2, Omicron BA.5, and Omicron XBB). First-HAI and mortality rates were calculated per 1000 patient-days. Predictors of first-HAI occurrence were investigated using a multivariable Fine–Gray regression model considering death as a competing event. Among 355 admitted patients, 27.3% experienced at least one HAI, and 49.6% died. Patient characteristics varied over time, with older and more complex cases in the later phases, while HAI and mortality rates were higher in the first year. Pathogens responsible for HAIs varied over time, with first Acinetobacter baumannii and then Klebsiella pneumoniae being progressively predominant. Multivariable analysis confirmed that, compared to Alpha, admission during the Omicron BA.1, BA.2, BA.5, and XBB periods was associated with lower hazards of HAI. Despite worsening COVID-19 patient conditions, late-phase HAI rates decreased, likely due to evolving pathogen characteristics, improved immunity, but also better clinical management, and adherence to infection prevention practices. Enhanced HAI prevention in emergency situations is crucial. Full article

Staphylococcus species are widespread in poultry environments and can cause various infections, often when the host’s defences are compromised. This manuscript reports on a co-infection of chickens with Staphylococcus lentus and Staphylococcus aureus associated with an outbreak of arthritis, synovitis, and osteomyelitis in an organic broiler breeder flock in Austria. Clinically, the affected flock showed weakness, lethargy, lameness, and increased mortality. Post-mortem examinations identified purulent arthritis and femoral head necrosis. Bacteriological analysis using MALDI-TOF MS identified both S. aureus and S. lentus in the affected joints. Antibiotic resistance testing revealed significant resistance, particularly in S. lentus. Histological analysis showed severe inflammation and bacterial colonies in the joints. While S. aureus is a common pathogen in poultry, S. lentus is less frequently reported. This study emphasises the need for detailed bacterial characterisation in outbreaks to better understand the role of less common pathogens like S. lentus. Further research is necessary to elucidate the impact of S. lentus on poultry health and its role in causing arthritis and synovitis, highlighting the importance of comprehensive investigation in such outbreaks. Full article

Background: Alveolar bone augmentation is a complex process influenced by a multitude of factors. The materials applied in augmentation procedures must be confirmed as non-toxic, and their physicochemical properties should allow proper bone reconstruction. The specifics of oral surgical procedures require the use of regenerative biomaterials with antimicrobial properties. This study focuses on the physicochemical characteristics of chosen nanosized biomaterials, as well as their cytotoxicity and antimicrobial properties. Methods: nanosized hydroxyapatite and fluorapatite (abbreviated as nHAp and nFAp) pellets were manufactured using a microwave hydrothermal synthesis method. The impact on Candida albicans, Streptococcus mutans, and Lactobacillus rhamnosus strains activity and adherence to apatites was tested. Cytotoxic evaluation was performed based on the differentiation process of MC3T3 cells. The effectiveness of MC3T3 differentiation was confirmed by Alizarin Red staining. Results: Contact with both biomaterials caused a reduction in the mean microbial count of S. mutans and C. albicans strains, as observed. Studied biomaterials demonstrated enhanced proliferation of MC3T3 cells, with the exception of the 1:1 nFAp concentration. Conclusions: Both biomaterials enhance the proliferation of fibroblasts and limit the activity of specific oral pathogens in vitro. The research clearly demonstrates the advantage of nFAp over nHAp, with a notable reduction in microbial count of Candida albicans and Streptococcus mutans over time. The lowest microbial count reduction was observed in the case of L. rhamnosus. Further research is required in order to fully understand the specifics of nHAp and nFAp antimicrobial action. However, the results were found to be more favourable for nFAp biomaterial. Full article

Environmental disasters are extreme environmental processes such as earthquakes, volcanic eruptions, landslides, tsunamis, floods, cyclones, storms, wildfires and droughts that are the consequences of the climate crisis due to human intervention in the environment. Their effects on human health have alarmed the global scientific community. Among them, autoimmune diseases, a heterogeneous group of disorders, have increased dramatically in many parts of the world, likely as a result of changes in our exposure to environmental factors. However, only a limited number of studies have attempted to discover and analyze the complex association between environmental disasters and autoimmune diseases. This narrative review has therefore tried to fill this gap. First of all, the activation pathways of autoimmunity after environmental disasters have been analyzed. It has also been shown that wildfires, earthquakes, desert dust storms and volcanic eruptions may damage human health and induce autoimmune responses to inhaled PM2.5, mainly through oxidative stress pathways, increased pro-inflammatory cytokines and epithelial barrier damage. In addition, it has been shown that heat stress, in addition to increasing pro-inflammatory cytokines, may also disrupt the intestinal barrier, thereby increasing its permeability to toxins and pathogens or inducing epigenetic changes. In addition, toxic volcanic elements may accelerate the progressive destruction of myelin, which may potentially trigger multiple sclerosis. The complex and diverse mechanisms by which vector-borne, water-, food-, and rodent-borne diseases that often follow environmental diseases may also trigger autoimmune responses have also been described. In addition, the association between post-disaster stress and the onset or worsening of autoimmune disease has been demonstrated. Given all of the above, the rapid restoration of post-disaster health services to mitigate the flare-up of autoimmune conditions is critical. Full article