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Veterinary Microbiology Sep 2023Trueperella pyogenes (T. pyogenes) could cause zoonotic disease in various mammals, resulting in significant economic losses. Due to the lack of effective vaccine and...
Trueperella pyogenes (T. pyogenes) could cause zoonotic disease in various mammals, resulting in significant economic losses. Due to the lack of effective vaccine and the emergence of bacterial resistance, there is a big need for new and improved vaccines. In this study, the non-hemolytic pyolysin mutant (PLOW497F), fimbriae E (FimE) and a truncated cell wall protein (HtaA-2) were selected to generate single or multivalent protein vaccines and their efficacies against lethal T. pyogenes challenge were evaluated in a mouse model. The results showed that the levels of specific antibody were significantly higher than the PBS control group after the booster vaccination. Compared to PBS treated mice, vaccinated mice had upregulated expressions of the inflammatory cytokine genes after the first vaccination. There was a downward trend thereafter, but return to the similar or even higher levels after challenge. Furthermore, co-immunization with rFimE or rHtaA-2 could significantly enhance the anti-hemolysis antibodies induced by rPLOW497F. The supplement of rHtaA-2 induced higher agglutinating antibodies compared with single administration with rPLOW497F or rFimE. Apart from these, the pathological lesions of lung were alleviated in rHtaA-2, rPLOW497F or their combinations immunized mice. Notably, immunization with rPLOW497F, rHtaA-2, combinations of rPLOW497F and rHtaA-2 or rHtaA-2 and rFimE completely protected mice from challenge, whereas the PBS immunized mice could not survive past 1 day post challenge. Thus, PLOW497F and HtaA-2 might be useful in developing efficient vaccines to prevent T. pyogenes infection.
Topics: Animals; Mice; Bacterial Proteins; Bacterial Toxins; Hemolysin Proteins; Bacterial Vaccines; Mammals
PubMed: 37307768
DOI: 10.1016/j.vetmic.2023.109810 -
Microbiology Resource Announcements Jan 2023The genus is constantly growing as novel species are identified. In particular, harbor seals have proven to be a common reservoir for bacteria of this genus. Here, we...
The genus is constantly growing as novel species are identified. In particular, harbor seals have proven to be a common reservoir for bacteria of this genus. Here, we announce the complete genome sequence of another species-namely, Arcanobacterium pinnipediorum strain DSM 28752, isolated from a harbor seal.
PubMed: 36598257
DOI: 10.1128/mra.01180-22 -
IDCases 2023to describe a case of severe sepsis and complicated bacteremia caused by cases in the literature.
OBJECTIVE
to describe a case of severe sepsis and complicated bacteremia caused by cases in the literature.
CASE SUMMARY
A 26-year-old gentleman with a history of epilepsy presented with symptoms of sore throat, productive cough, periumbilical abdominal pain, watery diarrhea, nausea and vomiting, subjective fevers along with progressive jaundice for seven days. The patient had acute fulminant liver failure, septic shock, and Multi-organ failure. He required vasopressors, underwent intubation, and had grown in the blood and Bronchoalveolar lavage samples. He developed a peritonsillar abscess and cavitary pneumonia and required chest tube drainage followed by thoracotomy for hemothorax. The patient improved on Ampicillin-Sulbactam treatment and was treated with a total antibiotic duration of 6 weeks. He fully improved on post-discharge follow-up.
DISCUSSION
Arcanobacterium haemolyticum is a Gram-positive (sometimes Gram variable), catalase-negative facultatively anaerobic, non-motile, non-spore-forming, and variably β-hemolytic and is known to be a cause of pharyngitis and skin and soft tissue infections. Rarely A. Haemolyticum can be associated with severe systemic infections such as infective endocarditis, systemic abscesses, osteomyelitis, and septicemia. In previous literature reviews, the source of A. haemolyticum depended on the host, and pharyngeal and upper respiratory sources were likely to be associated with immunocompetent hosts.
CONCLUSION
A. haemolyticum should be included in the differential diagnosis of bacterial pharyngitis complicated by severe systemic illness. Penicillins are the most commonly used antibiotics for treating A. haemolyticum bacteremia, and macrolides can be used for Penicillin's treatment failure.
PubMed: 36579145
DOI: 10.1016/j.idcr.2022.e01645 -
Tropical Animal Health and Production Oct 2022Uterine diseases are prevalent in camels and lead to economic losses because of decreased fertility. The aim of this study is to look into the expression patterns of...
Uterine diseases are prevalent in camels and lead to economic losses because of decreased fertility. The aim of this study is to look into the expression patterns of acute-phase proteins (APPs) and inflammatory cytokines in dromedary camels with clinical endometritis (CE) to highlight their role in the immune pathogenesis of the disease. Moreover, to identify the use of these parameters as a complementary tool for CE screening as well as investigate the efficacy of ceftiofur antibiotic, APPs and inflammatory cytokines were estimated in camels with CE. Values of APPs (Hp, SAA, and Fg), pro-inflammatory (IFN-γ, TNF-α, IL-1α, IL-1β, and IL-6), and anti-inflammatory cytokines (IL-10) were higher in camels with CE than in healthy controls (P < 0.05). The strongest correlations were observed between HP and IFN-γ (r = 0.73) and IL-1β and IL-6 (r = 0.73), while the weakest correlations were observed between Fg and IFN-γ (r = 0.25). Corynebacterium pyogenes and Arcanobacterium pyogenes were the most common pathogens involved in the etiology of CE. All investigated biomarkers demonstrated a high degree of recognition between CE camel and healthy controls (AUC was > 0.90). A higher proportion of camels with CE that were treated with ceftiofur (90%, P < 0.0001) scored clinical cures after the first dose, while 10% required a second dose. In conclusion, CE causes increased APPs and inflammatory cytokine biomarkers, indicating a significant acute phase response in diseased camels with CE. These changes in biomarkers could be beneficial for understanding the immune pathogenesis of CE in dromedary camels, clinical practice, and basic clinical research.
Topics: Female; Animals; Endometritis; Camelus; Cytokines; Acute-Phase Proteins; Interleukin-10; Tumor Necrosis Factor-alpha; Interleukin-6; Biomarkers; Anti-Bacterial Agents
PubMed: 36282373
DOI: 10.1007/s11250-022-03356-8 -
International Journal of Systematic and... Oct 2022A polyphasic taxonomic study was performed on an unidentified previously described -like Gram-positive strain 2701 isolated from an anal swab of a dead male harbour...
A polyphasic taxonomic study was performed on an unidentified previously described -like Gram-positive strain 2701 isolated from an anal swab of a dead male harbour seal. Comparative 16S rRNA sequencing showed that the bacterium belonged to the genus in the family . The genome sequence of the strain was obtained by Borowiak . [1]. The genome had a G+C content of 49 mol% and a total length of 1.94 Mb. The presence of the major menaquinone MK-9(H) supported the affiliation of the isolate with the genus . The polar lipid profile consisted of diphosphatidylglycerol and an unidentified phospholipid as major components and two unidentified lipids, a further unidentified phospholipid, two unidentified phosphoglycolipids as well as phosphatidylglycerol. The major fatty acids were C, C and C. Biochemical and phylogenetic analyses clearly distinguished the isolate from other members of the genus and closely related other species. Based on these results, it is proposed that the unknown sp. strain 2701 should be classified as representing a novel species with the name sp. nov. The type strain is 2701 (=DSM 112952=LMG 32446).
Topics: Animals; Male; Arcanobacterium; RNA, Ribosomal, 16S; Phoca; Phylogeny; Base Composition; Bacterial Typing Techniques; Vitamin K 2; DNA, Bacterial; Cardiolipins; Sequence Analysis, DNA; Fatty Acids; Phospholipids
PubMed: 36264671
DOI: 10.1099/ijsem.0.005573 -
Animal Reproduction 2022The purpose of this study is to investigate the role of some oxidative stress (OS), ceruloplasmin (Cp), and neopterin (NPT) as diagnostic biomarkers for dromedary camels...
The purpose of this study is to investigate the role of some oxidative stress (OS), ceruloplasmin (Cp), and neopterin (NPT) as diagnostic biomarkers for dromedary camels endometritis as well as to explore the impact of ceftiofur treatment on endometritis. Camels were categorized into two groups; healthy control group (n = 20) and endometritis group (n = 60). She-camels with clinical signs of endometritis (CE) received 6.6 mg/kg BW of ceftiofur (i/m). On days 7, and 14, she-camels were evaluated and clinical cure or failure to cure was determined. The comparison of the groups for OS demonstrated that endometritis caused an increase in serum malondialdehyde (sMDA), Cp, and NPT levels (P<0.05), but decreased serum levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) (P<0.05). The most prevalent pathogens involved in the etiology of CE are All examined biomarkers demonstrated a high degree of recognition between CE camel and healthy controls (the area under the curve (AUC) was 95.9 for NPT). A higher proportion of camels with CE that were treated with ceftiofur (90%, P<0.0001) showed clinical cure by the first dose, while 10% required a second dose. In conclusion, CE causes increased oxidative reactions and decreased antioxidant defense competence. Subsequently, the alteration in that balance that was represented by the biomarkers of OS could be beneficial for clinical practice and basic clinical research. Additionally, all trials demonstrated the efficacy of ceftiofur for the treatment of CE in she-camel.
PubMed: 36156882
DOI: 10.1590/1984-3143-AR2022-0035 -
Tropical Doctor Oct 2022formerly known as is a Gram positive bacilli. It is a fastidious, facultative anerobic, catalase negative, beta haemolytic and non motile bacterium. Gram positive...
formerly known as is a Gram positive bacilli. It is a fastidious, facultative anerobic, catalase negative, beta haemolytic and non motile bacterium. Gram positive bacilli are usually considered to be non-pathogenic as the majority are part of normal flora of human skin and mucous membranes. Hence, diagnosis of such infection and its treatment may be delayed by a failure of recognition. However, this bacterium has been implicated in wound, superficial and deep-seated soft tissue infections, endocarditis, osteomyelitis, meningitis, pneumonia, and also septicemia. The early diagnostic evaluation of this organism is emphasized. We report a case series which illustrates the significance of in skin and soft tissue infections.
Topics: Actinomycetales Infections; Arcanobacterium; Catalase; Humans; Soft Tissue Infections
PubMed: 35892166
DOI: 10.1177/00494755221097506 -
Frontiers in Immunology 2022() is a commensal and an opportunistic pathogen of animals. This organism can cause inflammatory diseases, such as pneumonia, mastitis and endometritis in hosts....
() is a commensal and an opportunistic pathogen of animals. This organism can cause inflammatory diseases, such as pneumonia, mastitis and endometritis in hosts. However, the molecular basis for the pro-inflammatory properties of this organism is still largely unknown. In the current study, using murine macrophages as model, the ability of to induce pyroptosis was first determined. Then, pyolysin (PLO), a cholesterol-dependent cytolysin secreted by , was found to be closely related to -induced pyroptosis. Next, our work showed that PLO can form pores in the cell membrane, leading to the efflux of potassium (K), NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated caspase-1 activation, and gasdermin D (GSDMD) cleavage. Inhibition of the K/NLRP3/caspase-1/GSDMD pathway abolished and PLO-induced IL-1β release. Taken together, these results indicate -induced inflammation is related to PLO-induced pyroptosis and IL-1β release. Our work shed light on the pathogenesis of and the interaction between and hosts' immune system.
Topics: Animals; Bacterial Proteins; Bacterial Toxins; Caspase 1; Female; Hemolysin Proteins; Macrophages; Mice; NLR Family, Pyrin Domain-Containing 3 Protein; Potassium; Pyroptosis
PubMed: 35371034
DOI: 10.3389/fimmu.2022.832458 -
Frontiers in Immunology 2022Many species of bacteria produce toxins such as cholesterol-dependent cytolysins that form pores in cell membranes. Membrane pores facilitate infection by releasing...
Many species of bacteria produce toxins such as cholesterol-dependent cytolysins that form pores in cell membranes. Membrane pores facilitate infection by releasing nutrients, delivering virulence factors, and causing lytic cell damage - cytolysis. Oxysterols are oxidized forms of cholesterol that regulate cellular cholesterol and alter immune responses to bacteria. Whether oxysterols also influence the protection of cells against pore-forming toxins is unresolved. Here we tested the hypothesis that oxysterols stimulate the intrinsic protection of epithelial cells against damage caused by cholesterol-dependent cytolysins. We treated epithelial cells with oxysterols and then challenged them with the cholesterol-dependent cytolysin, pyolysin. Treating HeLa cells with 27-hydroxycholesterol, 25-hydroxycholesterol, 7α-hydroxycholesterol, or 7β-hydroxycholesterol reduced pyolysin-induced leakage of lactate dehydrogenase and reduced pyolysin-induced cytolysis. Specifically, treatment with 10 ng/ml 27-hydroxycholesterol for 24 h reduced pyolysin-induced lactate dehydrogenase leakage by 88%, and reduced cytolysis from 74% to 1%. Treating HeLa cells with 27-hydroxycholesterol also reduced pyolysin-induced leakage of potassium ions, prevented mitogen-activated protein kinase cell stress responses, and limited alterations in the cytoskeleton. Furthermore, 27-hydroxycholesterol reduced pyolysin-induced damage in lung and liver epithelial cells, and protected against the cytolysins streptolysin O and α-hemolysin. Although oxysterols regulate cellular cholesterol by activating liver X receptors, cytoprotection did not depend on liver X receptors or changes in total cellular cholesterol. However, oxysterol cytoprotection was partially dependent on acyl-CoA:cholesterol acyltransferase (ACAT) reducing accessible cholesterol in cell membranes. Collectively, these findings imply that oxysterols stimulate the intrinsic protection of epithelial cells against pore-forming toxins and may help protect tissues against pathogenic bacteria.
Topics: Bacteria; Bacterial Proteins; Bacterial Toxins; Epithelial Cells; HeLa Cells; Hemolysin Proteins; Humans; Oxysterols; Virulence Factors
PubMed: 35154132
DOI: 10.3389/fimmu.2022.815775 -
Molecular and Cellular Probes Apr 2022The first description of Trueperella (T.) abortisuis was presented in Japan in 2009 by Azuma and colleagues. In the current study, eight T. abortisuis strains were...
The first description of Trueperella (T.) abortisuis was presented in Japan in 2009 by Azuma and colleagues. In the current study, eight T. abortisuis strains were identified by a newly developed loop-mediated isothermal amplification (LAMP) assay based on the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) encoding gene gap. Two T. abortisuis strains were obtained from prepuce of a seven-month-old boar and pooled foetal stomach contents in the United Kingdom, while the other six T. abortisuis strains were recovered from aborted foetal material of six pigs from a single farm in Germany. The developed LAMP assay showed an analytical sensitivity of 22 pg μLT. abortisuis DNA. T. abortisuis DSM 19515 and field strain T. abortisuis P504054/19/1 were directly detectable in artificially contaminated vaginal swabs up to concentrations of 980 CFU and 770 CFU per swab, respectively. There was no cross reactivity with control strains representing six species of genus Trueperella and six species of the closely related genus Arcanobacterium and Schaalia (Actinomyces) hyovaginalis. Further field research is required to determine the usefulness of the designed LAMP assay for identifying T. abortisuis isolated from pigs of various origins and from test samples directly obtained at farm level.
Topics: Actinomycetaceae; Animals; Arcanobacterium; Female; Male; Molecular Diagnostic Techniques; Nucleic Acid Amplification Techniques; RNA, Ribosomal, 16S; Sensitivity and Specificity; Swine
PubMed: 35131429
DOI: 10.1016/j.mcp.2022.101795