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BMC Microbiology Jan 2024Uterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and...
BACKGROUND
Uterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and economic losses. However, the bacteria responsible for uterine infections have not been adequately studied, nor has the antibiotic susceptibility of the causative bacteria been frequently tested in Ethiopia. This study aims to estimate the cumulative incidence of uterine infections in postpartum dairy cows, identify bacterial causes and determine antimicrobial susceptibility profile of the isolated bacteria.
METHODS
A prospective cohort study was conducted in which 236 cows from 74 dairy farms were monitored biweekly from calving to 90 days postpartum for metritis, endometritis and other disorders. Aseptic uterine swab samples were collected from 40 cows with uterine infections. The samples were cultured, and the isolated bacteria were tested for antimicrobial susceptibility using the disk diffusion method.
RESULTS
Out of 236 cows monitored during the postpartum phase, 45 (19.1%) were found to have contracted uterine infection. The cumulative incidence of metritis was 11.4% (n = 27), while the cumulative incidence of endometritis was 7.6% (n = 18). Of the 40 cultured swab samples, 29 (72.5%) had one or more bacteria isolated. The most commonly isolated bacteria were Escherichia coli (45%), coagulase-positive staphylococci (30%), and Klebsiella spp. (22.5%). Other bacterial spp, including Arcanobacterium pyogenes (12.5%), Fusobacterium spp. (12.5%), Enterobacter aerogenes (12.5%), coagulase-negative staphylococci (12.5%), Streptococcus spp. (7.5%), Salmonella spp, (5%) Proteus spp (5%) and Pasteurella spp (2.5%) were also isolated. All of the isolated bacteria demonstrated resistance to at least one of the antimicrobials tested. Multidrug resistance was observed in E. coli, Klebsiella spp., A. pyogenes, and Fusobacterium spp. Gentamicin was found to be the most effective antimicrobial against all bacteria tested, while tetracycline was the least effective of all.
CONCLUSION
The study found that a significant proportion of cows in the population were affected by uterine infections and the isolated bacteria developed resistance to several antimicrobials. The study emphasizes the need for responsible use of antimicrobials to prevent the emergence of antimicrobial resistance. It also highlights the importance of raising awareness among dairy farmers to avoid the indiscriminate use of antibiotics and its consequences.
Topics: Humans; Female; Cattle; Animals; Endometritis; Anti-Bacterial Agents; Incidence; Escherichia coli; Uterus; Prospective Studies; Coagulase; Ethiopia; Cattle Diseases; Drug Resistance, Bacterial; Bacteria; Postpartum Period
PubMed: 38172685
DOI: 10.1186/s12866-023-03160-w -
Virulence 2018Trueperella pyogenes (T. pyogenes) is an important opportunistic pathogen. Pyolysin (PLO) importantly contributes to the pathogenicity of T. pyogenes. However, the...
UNLABELLED
Trueperella pyogenes (T. pyogenes) is an important opportunistic pathogen. Pyolysin (PLO) importantly contributes to the pathogenicity of T. pyogenes. However, the relationship between the structure and function and the virulence of PLO is not well documented. In the current study, recombinant PLO (rPLO) and three rPLO mutants were prepared. rPLO D238R, a mutant with the 238th aspartic acid replaced with an arginine, showed impairment in oligomerization activity on cholesterol-containing liposome and pore-forming activity on sheep red blood cell membrane. Further study employing the prepared mutants confirmed that the pore-forming activity of PLO is essential for inducing excessive inflammation responses in mice by upregulating the expression levels of IL-1β, TNF-α, and IL-6. By contrast, rPLO P499F, another mutant with impaired cell membrane binding capacity, elicited an inflammation response that was dependent on pathogen-associated molecular pattern (PAMP) activity, given that the mutant significantly upregulated the expression of IL-10 in macrophages and in mice, whereas rPLO did not. Results indicated that domain 1 of the PLO molecule plays an important role in maintaining pore-forming activity. Moreover, the PLO pore-forming activity and not PAMP activity is responsible for the inflammation-inducing effect of PLO. The results of this study provided new information for research field on the structure, function, and virulence of PLO.
ABBREVIATIONS
T. pyogenes: Trueperella pyogenes; PLO: Pyolysin; rPLO: recombinant PLO; PAMP: pathogen-associated molecular pattern; CDCs: cholesterol-dependent cytolysins; PLY: pneumolysin; NLRP3: NLR family pyrin domain containing protein 3; PRRs: pattern recognition receptors; Asp: aspartic acid; TLR4: Toll-like receptor 4; Arg: arginine; Asn: asparagine; IPTG: Isopropyl-β-d-thiogalactoside; PBS: phosphate-buffered saline; sRBCs: sheep red blood cells; TEM: Transmission electron microscopy; RBCM: red blood cell membrane; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; NC membrane: nitrocellulose membrane; SDS-AGE: dodecyl sulfate agarose gel electrophoresis; MDBK cells: Madin-Darby bovine kidney cells; RPMI-1640 medium: Roswell Park Memorial Institute-1640 medium; FBS: fetal bovine serum; BMDMs: bone marrow-derived macrophages; TNF-α: tumor necrosis factor α; IL-1β: interleukin-1β; IFN-γ: interferon-γ; TGF-β: transforming growth factor-β; ELISA: enzyme-linked immunosorbent assay.
Topics: Actinomycetaceae; Amino Acid Substitution; Animals; Arginine; Aspartic Acid; Bacterial Proteins; Bacterial Toxins; Cattle; Cell Line; Erythrocyte Membrane; Female; Hemolysin Proteins; Hemolysis; Inflammation; Interleukin-10; Interleukin-1beta; Interleukin-6; Mice; Mice, Inbred BALB C; Mutation; Pore Forming Cytotoxic Proteins; Random Allocation; Recombinant Proteins; Sheep; Tumor Necrosis Factor-alpha; Virulence
PubMed: 30067143
DOI: 10.1080/21505594.2018.1491256 -
Kansas Journal of Medicine Feb 2018
PubMed: 29844849
DOI: No ID Found -
The Pan African Medical Journal 2016Arcanobacterium hemolyticum (A.haemolyticum) is a gram-positive bacillus. Man is the primary environmental reservoir. It is essentially an opportunistic pathogen in...
Arcanobacterium hemolyticum (A.haemolyticum) is a gram-positive bacillus. Man is the primary environmental reservoir. It is essentially an opportunistic pathogen in immunocompromised patients and may be responsible for infections of the skin and pharynx in healthy subjects, especially in children and adolescents. It can cause superinfections of chronic ulcers, but occasionally it causes invasive infections. Its isolation from culture samples is always difficult because it simulates many bacteria to which it is often associated in pathological products. There are not recommendations concerning the study of its antibiotics sensitivity. Arcanobacterium Bacteremia are rare to our knowledge, only sixteen case reports have been described in the literature. We here report another case of a patient with A.haemolyticum bacteremia secondary to superinfection of gluteal eschars.
Topics: Actinomycetales Infections; Aged; Arcanobacterium; Bacteremia; Fatal Outcome; Humans; Male; Pressure Ulcer
PubMed: 28154720
DOI: 10.11604/pamj.2016.25.28.6948 -
Toxins May 2018Arcanolysin, produced by the human pathogen , is a cholesterol-dependent cytolysin. To mediate the pore-formation process, arcanolysin is secreted by and then must...
Arcanolysin, produced by the human pathogen , is a cholesterol-dependent cytolysin. To mediate the pore-formation process, arcanolysin is secreted by and then must interact with cholesterol embedded within a host membrane. However, arcanolysin must compete with membrane components, such as the phospholipid sphingomyelin, to interact with cholesterol and form pores. Cholesterol forms transient hydrogen bonds with the extracellular portion of sphingomyelin, shielding cholesterol from extracellular factors, including arcanolysin. also produces a sphingomyelin-specific phospholipase D, which removes the choline head from sphingomyelin, leaving cyclic-ceramide phosphate and eliminating the potential for cholesterol sequestration. We hypothesized that the enzymatic activity of phospholipase D decreases sphingomyelin-mediated cholesterol sequestration and increases cholesterol accessibility for arcanolysin. Using purified arcanolysin and phospholipase D, we demonstrate that the enzymatic activity of phospholipase D is necessary to promote arcanolysin-mediated hemolysis in both time- and concentration-dependent manners. Phospholipase D promotion of arcanolysin-mediated cytotoxicity was confirmed in Detroit 562 epithelial cells. Furthermore, we determined that incubating phospholipase D with erythrocytes corresponds with an increase in the amount of arcanolysin bound to host membranes. This observation suggests that phospholipase D promotes arcanolysin-mediated cytotoxicity by increasing the ability of arcanolysin to bind to a host membrane.
Topics: Arcanobacterium; Cell Line, Tumor; Cholesterol; Erythrocytes; Hemolysis; Humans; Perforin; Phospholipase D; Sphingomyelins
PubMed: 29882842
DOI: 10.3390/toxins10060213 -
Microbiology Resource Announcements Jan 2024Many species of the genus are known as opportunistic pathogens and have been isolated in association with infectious diseases in humans and animals. Here, we present...
Many species of the genus are known as opportunistic pathogens and have been isolated in association with infectious diseases in humans and animals. Here, we present the complete genome sequence of another opportunistic pathogenic representative, namely , isolated from the otitis externa of an English bulldog.
PubMed: 38099684
DOI: 10.1128/mra.00624-23 -
International Journal of Molecular... Jun 2024is an important opportunistic pathogenic bacterium widely distributed in the environment. Pyolysin (PLO) is a primary virulence factor of and capable of lysing many...
is an important opportunistic pathogenic bacterium widely distributed in the environment. Pyolysin (PLO) is a primary virulence factor of and capable of lysing many different cells. PLO is a member of the cholesterol-dependent cytolysin (CDC) family of which the primary structure only presents a low level of homology with other members from 31% to 45%. By deeply studying PLO, we can understand the overall pathogenic mechanism of CDC family proteins. This study established a mouse muscle tissue model infected with recombinant PLO (rPLO) and its single-point mutations, rPLO N139K and rPLO F240A, and explored its mechanism of causing inflammatory damage. The inflammatory injury abilities of rPLO N139K and rPLO F240A are significantly reduced compared to rPLO. This study elaborated on the inflammatory mechanism of PLO by examining its unit point mutations in detail. Our data also provide a theoretical basis and practical significance for future research on toxins and bacteria.
Topics: Animals; Point Mutation; Mice; Hemolysin Proteins; NLR Family, Pyrin Domain-Containing 3 Protein; Bacterial Proteins; Inflammation; Potassium; Signal Transduction; Bacterial Toxins; Inflammasomes; Humans
PubMed: 38928408
DOI: 10.3390/ijms25126703 -
Japanese Journal of Infectious Diseases Nov 2017Trueperella bernardiae (T.bernardiae) is a gram-positive curved rod that is considered an uncommon pathogen involved in few infections. The true incidence of infections...
Trueperella bernardiae (T.bernardiae) is a gram-positive curved rod that is considered an uncommon pathogen involved in few infections. The true incidence of infections with this bacterium, and the clinical implications, remain unknown. We report 2 cases of wound infections in 2 patients who underwent different surgical procedures, although in the second case the microorganism was isolated in mixed culture. Culture of wound secretions resulted in isolation of T. bernardiae. Treatment was performed and resolution of the infections was documented.
Topics: Actinomycetales Infections; Aged; Anti-Bacterial Agents; Arcanobacterium; Biomarkers; Female; Humans; Male; Symptom Assessment; Treatment Outcome; Wound Infection
PubMed: 28890519
DOI: 10.7883/yoken.JJID.2017.221 -
PloS One 2016Fur Animal Epidemic Necrotic Pyoderma (FENP) is a severe, often lethal infectious disease affecting all three fur animal species: mink (Neovision vision), foxes (Vulpes...
Fur Animal Epidemic Necrotic Pyoderma (FENP) is a severe, often lethal infectious disease affecting all three fur animal species: mink (Neovision vision), foxes (Vulpes lagopus) and finnraccoons (Nyctereutes procyonoides). Previous studies showed an association between Arcanobacterium phocae and FENP. An experimental infection was conducted to confirm the ability of A. phocae to infect mink either alone or concurrently with a novel Streptococcus sp. found together with A. phocae in many cases of FENP. Different inoculation methods were tested to study possible routes of transmission. Typical signs, and gross- and histopathological findings for FENP were detected when naïve mink were infected with the tissue extract of mink with FENP, using a subcutaneous/ intradermal infection route. Edema, hemorrhage, necrosis and pus formation were detected in the infection site. A pure culture preparation of A. phocae alone or concurrently with the novel Streptococcus sp. caused severe acute signs of lethargy, apathy and anorexia and even mortality. The histopathological findings were similar to those found in naturally occurring cases of FENP. In contrast, the perorally infected mink presented no clinical signs nor any gross- or histopathological lesions. This study showed that A. phocae is able to cause FENP. The study also indicated that predisposing factors such as the environment, the general condition of the animals, temperature and skin trauma contribute to the development of the disease.
Topics: Animals; Arcanobacterium; Edema; Environment; Foxes; Hemorrhage; Mink; Necrosis; Pilot Projects; Polymerase Chain Reaction; Pyoderma; Raccoon Dogs; Raccoons; Skin; Temperature
PubMed: 27973532
DOI: 10.1371/journal.pone.0168129 -
Microbiology Resource Announcements Sep 2020spp. are Gram-positive bacteria which can be found in a wide range of hosts and can be associated with disease in humans and animals. Here, we announce the complete...
spp. are Gram-positive bacteria which can be found in a wide range of hosts and can be associated with disease in humans and animals. Here, we announce the complete genome sequence of sp. strain 2701, isolated from a harbor seal from the North Sea.
PubMed: 32943560
DOI: 10.1128/MRA.00652-20