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Ultrasonics Sonochemistry Jan 2024Emodin was extracted from Rheum officinale Baill by ultrasound-assisted extraction (UAE), and ethanol was chosen as the suitable solvent through SEM and molecular...
Emodin was extracted from Rheum officinale Baill by ultrasound-assisted extraction (UAE), and ethanol was chosen as the suitable solvent through SEM and molecular dynamic simulation. Under the optimum conditions (power 541 W, time 23 min, liquid to material ratio 13:1 mL/g, ethanol concentration 83 %) predicted by RSM, the yield of emodin was 2.18 ± 0.11 mg/g. Moreover, ultrasound power and time displayed the significant effects on the extraction process. Extracting dynamics analysis indicated that the extraction process of emodin by UAE conformed to Fick's second diffusion law. The results of antibacterial experiments suggested that emodin can damage cell membrane and inhibit the expression of cps2A, sao, mrp, epf, neu and the hemolytic activity of S. suis. Biolayer interferometry and FT-IR multi-peak fitting assays demonstrated that emodin induced a secondary conformational shift in CcpA. Molecular docking and molecular dynamics confirmed that emodin bound to CcpA through hydrogen bonding (ALA248, GLU249, GLY129 and ASN196) and π-π T-shaped interaction (TYR225 and TYR130), and the mutation of amino acid residues affected the affinity of CcpA to emodin. Therefore, emodin inhibited the sugar utilization of S. suis through binding to CcpA, and CcpA may be a potential target to inhibit the growth of S. suis.
Topics: Emodin; Rheum; Streptococcus suis; Molecular Docking Simulation; Spectroscopy, Fourier Transform Infrared; Anti-Bacterial Agents; Ethanol
PubMed: 38150957
DOI: 10.1016/j.ultsonch.2023.106733 -
Animals : An Open Access Journal From... Dec 2023Necropsies can reveal herd problems or comorbidities that can lead to management corrections, improvements in animal performance, and better decision making....
Necropsies can reveal herd problems or comorbidities that can lead to management corrections, improvements in animal performance, and better decision making. Furthermore, the pattern and causes of mortality might differ when different systems are evaluated. The present study was conducted to establish the main causes of death in nursery pigs from different systems in Brazil, as well as the clinical, microbiological, and pathological aspects of these mortalities. Eighteen nurseries were analyzed (a total of 120,243 housed piglets), and 557 necropsies were performed. infection was the most prevalent cause of death (21.2%), followed by bacterial polyserositis (16.7%), chronic atrophic enteritis (13.5%), salmonellosis (8.8%), pneumonia (8.6%), and colibacillosis (6.1%). The increase in mortality rate in individual nurseries and, consequently, in the diagnoses was commonly associated with disease outbreaks. Infectious diseases constituted the largest portion of the diagnoses, making a great opportunity for improving production rates in herds. Moreover, the extensive range of observed diagnoses highlights the importance of conducting preliminary diagnostic investigations based on necropsy to determine the causes of death. This approach allows for the direction of complementary tests, which can diagnose agents with greater specificity. As a result, this allows for the implementation of more effective prevention and control strategies.
PubMed: 38136857
DOI: 10.3390/ani13243819 -
BMC Veterinary Research Dec 2023Accurate measurement of disease associated with endemic bacterial agents in pig populations is challenging due to their commensal ecology, the lack of disease-specific...
Detection and disease diagnosis trends (2017-2022) for Streptococcus suis, Glaesserella parasuis, Mycoplasma hyorhinis, Actinobacillus suis and Mycoplasma hyosynoviae at Iowa State University Veterinary Diagnostic Laboratory.
BACKGROUND
Accurate measurement of disease associated with endemic bacterial agents in pig populations is challenging due to their commensal ecology, the lack of disease-specific antemortem diagnostic tests, and the polymicrobial nature of swine diagnostic cases. The main objective of this retrospective study was to estimate temporal patterns of agent detection and disease diagnosis for five endemic bacteria that can cause systemic disease in porcine tissue specimens submitted to the Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) from 2017 to 2022. The study also explored the diagnostic value of specific tissue specimens for disease diagnosis, estimated the frequency of polymicrobial diagnosis, and evaluated the association between phase of pig production and disease diagnosis.
RESULTS
S. suis and G. parasuis bronchopneumonia increased on average 6 and 4.3%, while S. suis endocarditis increased by 23% per year, respectively. M. hyorhinis and A. suis associated serositis increased yearly by 4.2 and 12.8%, respectively. A significant upward trend in M. hyorhinis arthritis cases was also observed. In contrast, M. hyosynoviae arthritis cases decreased by 33% average/year. Investigation into the diagnostic value of tissues showed that lungs were the most frequently submitted sample, However, the use of lung for systemic disease diagnosis requires caution due to the commensal nature of these agents in the respiratory system, compared to systemic sites that diagnosticians typically target. This study also explored associations between phase of production and specific diseases caused by each agent, showcasing the role of S. suis arthritis in suckling pigs, meningitis in early nursery and endocarditis in growing pigs, and the role of G. parasuis, A. suis, M. hyorhinis and M. hyosynoviae disease mainly in post-weaning phases. Finally, this study highlighted the high frequency of co-detection and -disease diagnosis with other infectious etiologies, such as PRRSV and IAV, demonstrating that to minimize the health impact of these endemic bacterial agents it is imperative to establish effective viral control programs.
CONCLUSIONS
Results from this retrospective study demonstrated significant increases in disease diagnosis for S. suis, G. parasuis, M. hyorhinis, and A. suis, and a significant decrease in detection and disease diagnosis of M. hyosynoviae. High frequencies of interactions between these endemic agents and with viral pathogens was also demonstrated. Consequently, improved control programs are needed to mitigate the adverse effect of these endemic bacterial agents on swine health and wellbeing. This includes improving diagnostic procedures, developing more effective vaccine products, fine-tuning antimicrobial approaches, and managing viral co-infections.
Topics: Humans; Swine; Animals; Mycoplasma hyorhinis; Mycoplasma hyosynoviae; Streptococcus suis; Actinobacillus suis; Mycoplasma Infections; Iowa; Retrospective Studies; Universities; Swine Diseases; Arthritis; Endocarditis
PubMed: 38087358
DOI: 10.1186/s12917-023-03807-w -
Frontiers in Microbiology 2023An efficient and rapid immunochromatographic assay (ICA) has been engineered for the detection of (). The underpinning principle of this ICA test lies in the use of...
An efficient and rapid immunochromatographic assay (ICA) has been engineered for the detection of (). The underpinning principle of this ICA test lies in the use of polyclonal antibodies (pAbs) decorated with colloidal gold, which are specific to These pAbs were derived from rabbits immunized with type II histidine triad protein (HtpsC) and HtpsC-N of . The sensitivity of the ICA was noteworthy, identifying at bacterial concentrations as diminutive as 1.0 × 10 CFU/mL. Moreover, the assay demonstrated respectable specificity and did not indicate false positives for other bacterial species (, , , , , , or ). The assay was also capable of detecting multiple serotypes containing the gene, including serotypes 1-9, 12, 14, 16 and 23. Nonetheless, the detection of that lacks the gene remained beyond the capabilities of this assay. A simultaneous analysis of 16 samples utilizing PCR substantiated the reliability of the ICA test. The assay's results can be procured within a 15-min window, making it a suitable option for field application. Broadly, this study underscores the potential of the HtpsC protein as a target antigen for the detection of , and proposes that the HtpsC protein be evaluated further in other detection assays specific for .
PubMed: 38075933
DOI: 10.3389/fmicb.2023.1294368 -
International Journal of Molecular... Nov 2023() is a swine pathogen that can cause sepsis, meningitis, endocarditis, and other infectious diseases; it is also a zoonotic pathogen that has caused a global surge in...
() is a swine pathogen that can cause sepsis, meningitis, endocarditis, and other infectious diseases; it is also a zoonotic pathogen that has caused a global surge in fatal human infections. The widespread prevalence of multidrug-resistant strains and the decline in novel antibiotic candidates have necessitated the development of alternative antimicrobial agents. In this study, AVPL, the () phage lysin, was found to exhibit efficient bactericidal activity and broad lytic activity against multiple serotypes of . A final concentration of 300 μg/mL AVPL reduced counts by 4-4.5 log10 within 1 h in vitro. Importantly, AVPL effectively inhibited 48 h biofilm formation and disrupted preformed biofilms. In a mouse model, 300 μg/mouse AVPL protected 100% of mice from infection following the administration of lethal doses of multidrug-resistant type 2 (SS2) strain SC19, reduced the bacterial load in different organs, and effectively alleviated inflammation and histopathological damage in infected mice. These data suggest that AVPL is a valuable candidate antimicrobial agent for treating infections.
Topics: Animals; Swine; Humans; Mice; Bacteriophages; Aerococcus; Streptococcus suis; Streptococcal Infections; Bacteremia; Disease Models, Animal
PubMed: 38068990
DOI: 10.3390/ijms242316670 -
Scientific Reports Dec 2023Bordetella bronchiseptica poses a significant challenge in the context of respiratory infections, particularly in weanling pigs. In this study, we investigated the...
Bordetella bronchiseptica poses a significant challenge in the context of respiratory infections, particularly in weanling pigs. In this study, we investigated the impact of a novel targeted bacteriophage in controlling B. bronchiseptica challenge (BBC) in an experimental design involving five distinct treatment groups: NC (no challenge), PC (BBC challenge), BF (10 pfu bacteriophage/kg diet + BBC), BN (2 × 10 pfu/day bacteriophage by nasal spray + BBC), and AT (antibiotic + BBC). The experiment was conducted for 2 weeks. The highest turbinate score was observed in the PC. The BF treatment showed higher plasma IL (interleukine)-1β and IL-6 compared with the BN and AT treatments. Plasma concentrations of IL-1β were increased in the BF pigs compared with the BN, AT, and NC. Among the BBC groups, the PC treatment exhibited a higher abundance of Staphylococcus. aureus and B. bronchiseptica in the lung. A lower S. aureus, Streptococcus. suis, and B. bronchiseptica colonization was detected in the AT compared with the BF and BN treatments. The BF showed lower plasma zonulin compared with the BN and AT. A higher plasma concentration of superoxide dismutase was observed in the BF and AT compared with PC and BN. The BN influenced the glycine, serine-threonine metabolism; glycerolipid metabolism; glyoxylate-dicarboxylate metabolism; and arachidonic acid metabolism compared with the NC. In conclusion, nasal-sprayed bacteriophage effectively controlled B. bronchiseptica infection, however, their efficiency was lower than the antibiotic.
Topics: Animals; Swine; Bordetella bronchiseptica; Swine Diseases; Bacteriophages; Staphylococcus aureus; Bordetella Infections; Microbiota; Anti-Bacterial Agents
PubMed: 38066337
DOI: 10.1038/s41598-023-49248-1 -
MBio Jan 2024Phase variation allows a single strain to produce phenotypic diverse subpopulations. Phase-variable restriction modification (RM) systems are systems that allow for such...
The streptococcal phase-variable type I restriction modification system SsuCC20p dictates the methylome of impacting the transcriptome and virulence in a zebrafish larvae infection model.
Phase variation allows a single strain to produce phenotypic diverse subpopulations. Phase-variable restriction modification (RM) systems are systems that allow for such phase variation via epigenetic regulation of gene expression levels. The phase-variable RM system SsuCC20p was found in multiple streptococcal species and was acquired by an emerging zoonotic lineage of . We show that the phase variability of SsuCC20p is dependent on a recombinase encoded within the SsuCC20p locus. We characterized the genome methylation profiles of the different phases of SsuCC20p and demonstrated the consequential impact on the transcriptome and virulence in a zebrafish infection model. Acquiring mobile genetic elements containing epigenetic regulatory systems, like phase-variable RM systems, enables bacterial pathogens to produce diverse phenotypic subpopulations that are better adapted to specific (host) environments encountered during infection.
Topics: Animals; Streptococcus suis; Epigenesis, Genetic; DNA Restriction-Modification Enzymes; Zebrafish; Virulence; Larva; Epigenome; Transcriptome; Streptococcal Infections; Bacterial Proteins
PubMed: 38063379
DOI: 10.1128/mbio.02259-23 -
Scientific Reports Dec 2023This study aimed to determine the presence and characteristics of locally circulating strains of Streptococcus suis, the most important streptococcal pathogen in swine....
This study aimed to determine the presence and characteristics of locally circulating strains of Streptococcus suis, the most important streptococcal pathogen in swine. Oral swab samples were collected from pigs from 664 representative smallhold farms across nine provinces in the Philippines. Isolates were identified and characterized using PCR assays. The study revealed an isolation rate of 15.8% (105/664, 95% CI: 13.0-18.6) among the sampled farms. Two hundred sixty-nine (269) S. suis isolates were recovered from 119 unique samples. Serotype 31 was the most prevalent (50/269, 95% CI: 13.9-23.2) among the other serotypes identified: 5, 6, 8, 9, 10, 11, 15, 16, 17, 21, 27, 28, and 29. The detection of the three 'classical' S. suis virulence-associated genes showed that 90.7% (244/269, 95% CI: 87.2-94.2) were mrp/epf/sly Multilocus sequence typing (MLST) analysis further revealed 70 novel sequence types (STs). Notably, several local isolates belonging to these novel STs formed clonal complexes (CC) with S. suis strains recovered from Spain and USA, which are major pork-exporting countries to the Philippines. This study functionally marks the national baseline knowledge of S. suis in Philippines.
Topics: Swine; Animals; Multilocus Sequence Typing; Streptococcus suis; Philippines; Farms; Streptococcal Infections; Genotype; Swine Diseases; Genetic Variation
PubMed: 38040767
DOI: 10.1038/s41598-023-48406-9 -
Frontiers in Cellular and Infection... 2023() is widely acknowledged as a significant zoonotic pathogen in Southeast Asia and China, which has led to a substantial number of fatalities in both swine and humans....
() is widely acknowledged as a significant zoonotic pathogen in Southeast Asia and China, which has led to a substantial number of fatalities in both swine and humans. Despite the prevalent use of mice as the primary animal model to study pathogenesis, the substantial differences in the major histocompatibility complex (MHC) between humans and mice underscore the ongoing exploration for a more suitable and effective animal model. In this study, humanized transgenic HLA-A11/DR1 genotypes mice were used to evaluate the differences between humanized HLA and murine H2 in infection. Following intravenous administration of suspensions, we investigated bacterial load, cytokine profiles, pathological alterations, and immune cell recruitment in both Wild-type (WT) and humanized mice across different post-infection time points. Relative to WT mice, humanized mice exhibited heightened pro-inflammatory cytokines, exacerbated tissue damage, increased granulocyte recruitment with impaired resolution, notably more pronounced during the late infection stage. Additionally, our examination of bacterial clearance rates suggests that HLA-A11/DR1 primarily influences cell recruitment and mitochondrial reactive oxygen species (ROS) production, which affects the bacterial killing capacity of macrophages in the late stage of infection. The reduced IL-10 production and lower levels of regulatory T cells in humanized mice could underlie their compromised resolution ability. Intervention with IL-10 promotes bacterial clearance and inflammatory regression in the late stages of infection in transgenic mice. Our findings underscore the heightened sensitivity of HLA-A11/DR1 mice with impaired resolution to infection, effectively mirroring the immune response seen in humans during infection. The humanized HLA-A11/DR1 mice could serve as an optimal animal model for investigating the pathogenic and therapeutic mechanisms associated with sepsis and other infectious diseases.
Topics: Humans; Animals; Mice; Swine; Interleukin-10; Streptococcus suis; Serogroup; HLA-A11 Antigen; Mice, Transgenic; Immunity; Streptococcal Infections
PubMed: 38035330
DOI: 10.3389/fcimb.2023.1285055 -
Frontiers in Microbiology 2023The increase in antibiotic resistance of bacteria has become a major concern in clinical treatment. Silver nanoparticles (AgNPs) have significant antibacterial effects...
BACKGROUND
The increase in antibiotic resistance of bacteria has become a major concern in clinical treatment. Silver nanoparticles (AgNPs) have significant antibacterial effects against . Therefore, this study aimed to investigate the antibacterial activity and mechanism of action of AgNPs against multidrug-resistant .
METHODS
The effect of AgNPs on the morphology of multidrug-resistant was observed using scanning electron microscopy (SEM). Differentially expressed proteins were analyzed by iTRAQ quantitative proteomics, and the production of reactive oxygen species (ROS) was assayed by HDCF-DA staining.
RESULTS
SEM showed that AgNPs disrupted the normal morphology of multidrug-resistant and the integrity of the biofilm structure. Quantitative proteomic analysis revealed that a large number of cell wall synthesis-related proteins, such as penicillin-binding protein and some cell cycle proteins, such as the cell division protein FtsZ and chromosomal replication initiator protein DnaA, were downregulated after treatment with 25 μg/mL AgNPs. Significant changes were also observed in the expression of the antioxidant enzymes glutathione reductase, alkyl hydroperoxides-like protein, α/β superfamily hydrolases/acyltransferases, and glutathione disulfide reductases. ROS production in positively correlated with AgNP concentration.
CONCLUSION
The potential antibacterial mechanism of AgNPs may involve disrupting the normal morphology of bacteria by inhibiting the synthesis of cell wall peptidoglycans and inhibiting the growth of bacteria by inhibiting the cell division protein FtsZ and Chromosomal replication initiator protein DnaA. High oxidative stress may be a significant cause of bacterial death. The potential mechanism by which AgNPs inhibit biofilm formation may involve affecting bacterial adhesion and interfering with the quorum sensing system.
PubMed: 38033593
DOI: 10.3389/fmicb.2023.1293363