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JPMA. the Journal of the Pakistan... Apr 2023To characterise the biofilm matrix composition of a newly described Staphylococcus aureus biofilm phenotype.
OBJECTIVES
To characterise the biofilm matrix composition of a newly described Staphylococcus aureus biofilm phenotype.
METHOD
This experimental study was conducted at the Faculty of Pharmacy, Helwan University, Cairo, Egypt, from January 2021 to March 2022, and comprised methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus biofilm-forming clinical isolates which were allowed to construct biofilms under two distinct culture conditions; one a commonly used condition, and the other one a novel, more biologically-relevant condition. The formed biofilms were analysed for matrix composition through treatment with proteinase,sodium meta-periodate, and streptokinase. The efficacy of Cis-2-Decenoic acid and hamamelitannin on the biologically-relevant biofilms was evaluated using biofilm viability assay based on a colorimetric assay for measuring cell metabolic activity and scanning electron microscope imaging. Data was analysed using GraphPad Prism 5.01.
RESULTS
Of the 58 isolates, 45(77.6%) were methicillin-resistant Staphylococcus aureus and 13(22.4%) were methicillin susceptible Staphylococcus aureus. There was significant difference in responses to streptokinase, proteinase and sodium meta-periodate (p<0.05) among the differentially-developed biofilms in methicillin-resistant Staphylococcus aureus isolates. Regarding the methicillin-susceptible Staphylococcus aureus isolates, the differentially-developed biofilms showed significantly different liabilities to streptokinase only (p<0.05). Mean biofilm inhibition for Cis-2- Decenoic acid was 54.27±27.93% and mean biofilm dispersion was 71.92±11.59% while the corresponding valuesfor hamamelitannin were 83.03±13.95% and 70.48±7.116% against the newly described methicillin-resistant Staphylococcus aureus biofilm phenotype.
CONCLUSIONS
Applying biologically-relevant culture conditions on staphylococci biofilms and antibiofilm drugs is recommended.
Topics: Humans; Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus; Methicillin; Anti-Bacterial Agents; Staphylococcal Infections; Biofilms; Peptide Hydrolases; Phenotype; Streptokinase; Sodium; Microbial Sensitivity Tests
PubMed: 37482852
DOI: 10.47391/JPMA.EGY-S4-34 -
Annals of Saudi Medicine 2024Inevitably, the floors of mosques are contaminated with microorganisms, and the risk of pathogen transmission is probably high between the many visitors, but the issue...
BACKGROUND
Inevitably, the floors of mosques are contaminated with microorganisms, and the risk of pathogen transmission is probably high between the many visitors, but the issue has been infrequently studied.
OBJECTIVES
Investigate microorganism variety and risk of contamination on commonly used carpets and rosaries (prayer beads).
DESIGN
Cross-sectional.
SETTINGS
Mosques.
METHODS
This study was carried out in three different cities of Turkey in 2023, focusing on mosques located around hospitals. Forty mosques were included in the study and from each mosque 10 samples were collected from various parts of carpets and rosaries. The number of positive culture isolates were identified.
MAIN OUTCOME MEASURES
Diversity and distribution of microorganisms isolated from mosque carpets and rosaries; methicillin-resistance rates in .
SAMPLE SIZE
400 samples.
RESULTS
Growth was observed in 368 (92%) of 400 samples examined. The microorganisms isolated in the highest number were methicillin-susceptible coagulase negative (MSCoNS) (59.8%), (41%) and diphtheroids (31.3%). The rates of total growth (=.001), including diphtheroids (=.018), methicillin-resistant coagulase negative (P=.001), (=.036) and (=.002) rates were significantly higher in the rosary samples than carpet samples. At mosques in Tokat, a province center, 4 samples were positive for , two samples were positive for and one sample for methicillin-resistant (MRSA), and these were isolated from rosaries. 0.3% of isolates were MRSA.
CONCLUSION
As there is a high risk of contamination of carpets and prayer beads on the mosque floor with human flora, the use of appropriate hygiene practices is necessary. We also found some emerging bacteria in addition to the normal human flora.
LIMITATIONS
Our study was conducted in three provinces. Further studies might cover a wider geography.
Topics: Humans; Coagulase; Cross-Sectional Studies; Floors and Floorcoverings; Methicillin; Methicillin-Resistant Staphylococcus aureus
PubMed: 38615188
DOI: 10.5144/0256-4947.2024.67 -
Antimicrobial Agents and Chemotherapy May 1981We evaluated the distribution of methicillin into normal and damaged heart valves and the accuracy with which subcutaneous plastic chambers reflected tissue uptake of...
We evaluated the distribution of methicillin into normal and damaged heart valves and the accuracy with which subcutaneous plastic chambers reflected tissue uptake of this antibiotic. A total of 24 male New Zealand rabbits were given constant infusion doses of methicillin through central venous catheters. Five of these animals had their aortic and mitral valves damaged by catheterization of the left ventricle. A total of 19 rabbits had perforated plastic chambers inserted subcutaneously 7 to 10 days before methicillin infusion. In all animals more than 80% of the total infused dose of methicillin was accounted for in the serum, urine, and tissues. In the 12 animals infused to steady state (less than 7 h), the steady-state serum concentrations (11 to 120 micrograms/ml) were equal to the concentrations attained in either peritoneal or tissue chamber fluids. In the 12 animals sacrificed before 7 h, tissue chamber concentrations lagged behind serum and heart tissue concentrations in attaining steady state. Steady-state concentrations in normal heart valves and heart muscles failed to increase proportionally to increased constant infusion doses (8.7 to 87.2 mg/kg per h). The steady-state methicillin concentrations in fibrin-scarred heart valves were invariably higher than the steady-state concentrations in the normal right heart of the same animals (P less than 0.05). Tissue uptake of methicillin was altered in scarred heart valves as compared to normal heart valves, and large-volume subcutaneous tissue chambers misrepresented the uptake rate of methicillin into heart tissues and valves.
Topics: Animals; Aortic Valve; Body Fluids; Heart Valve Diseases; Heart Valves; Infusions, Parenteral; Male; Methicillin; Rabbits
PubMed: 7294768
DOI: 10.1128/AAC.19.5.836 -
International Journal of Molecular... Nov 2023Methicillin-sensitive () (MSSA) bacteremia remains a global challenge, despite the availability of antibiotics. Primary treatments include β-lactam agents such as...
Methicillin-sensitive () (MSSA) bacteremia remains a global challenge, despite the availability of antibiotics. Primary treatments include β-lactam agents such as cefazolin and flucloxacillin. Ongoing discussions have focused on the potential synergistic effects of combining these agents with rifampicin or fosfomycin to combat infections associated with biofilm formation. Managing staphylococcal infections is challenging due to antibacterial resistance, biofilms, and 's ability to invade and replicate within host cells. Intracellular invasion shields the bacteria from antibacterial agents and the immune system, often leading to incomplete bacterial clearance and chronic infections. Additionally, can assume a dormant phenotype, known as the small colony variant (SCV), further complicating eradication and promoting persistence. This study investigated the impact of antibiotic combinations on the persistence of 6850 and its stable small colony variant (SCV strain JB1) focusing on intracellular survival and biofilm formation. The results from the wild-type strain 6850 demonstrate that β-lactams combined with RIF effectively eliminated biofilms and intracellular bacteria but tend to select for SCVs in planktonic culture and host cells. Higher antibiotic concentrations were associated with an increase in the zeta potential of , suggesting reduced membrane permeability to antimicrobials. When using the stable SCV mutant strain JB1, antibiotic combinations with rifampicin successfully cleared planktonic bacteria and biofilms but failed to eradicate intracellular bacteria. Given these findings, it is reasonable to report that β-lactams combined with rifampicin represent the optimal treatment for MSSA bacteremia. However, caution is warranted when employing this treatment over an extended period, as it may elevate the risk of selecting for small colony variants (SCVs) and, consequently, promoting bacterial persistence.
Topics: Humans; Anti-Bacterial Agents; Staphylococcus aureus; Methicillin; Methicillin-Resistant Staphylococcus aureus; Rifampin; Staphylococcal Infections; Biofilms; beta-Lactams; Bacteremia; Microbial Sensitivity Tests
PubMed: 38003500
DOI: 10.3390/ijms242216308 -
Antimicrobial Agents and Chemotherapy Feb 1980Eight cephalosporins were tested for their activity against methicillin-susceptible and methicillin-resistant, coagulase-negative staphylococci and for their resistance...
Eight cephalosporins were tested for their activity against methicillin-susceptible and methicillin-resistant, coagulase-negative staphylococci and for their resistance to beta-lactamase from methicillin-resistant, coagulase-negative staphylococci. Susceptibility testing by the agar plate method was evaluated for the effect of inoculum size and duration of incubation. Methicillin-susceptible, coagulase-negative staphylococci were highly susceptible to the cephalosporins, with cephapirin and cepahlothin showing the greatest activity, followed by cefazolin and cefamandole. Methicillin-resistant, coagulase-negative staphylococci displayed nearly total cross-resistance to the cephalosporins. Resistance increased with increasing inoculum size. Beta-Lactamases produced by methicillin-resistant, coagulase-negative staphylococci had a minimal hydrolytic effect on cepahlothin, cephapirin, cefazolin, and cefamandole and no measurable effect on cefoxitin. There was no correlation between the anti-staphylococcal activity and resistance to beta-lactamases.
Topics: Cephalosporins; Coagulase; Methicillin; Microbial Sensitivity Tests; Penicillin Resistance; Staphylococcus; beta-Lactamases
PubMed: 6966906
DOI: 10.1128/AAC.17.2.179 -
Microbiological Research Nov 2021Biofilm formation by pathogenic bacteria as well as their resilience to antibiotic treatments are a major health problem. Here, we sequenced and analyzed the genome of...
Biofilm formation by pathogenic bacteria as well as their resilience to antibiotic treatments are a major health problem. Here, we sequenced and analyzed the genome of the clinical methicillin-resistant Staphylococcus aureus S1 (MRSA-S1) strain and established its sensitivity to the combination of methicillin and the leaderless two peptides enterocin DD14 (EntDD14). Such sensitivity was assessed in vitro based on the MIC/FIC values as well as on killing curves experiments. Moreover, combination of EntDD14 and methicillin was able to reduce the biofilm formation of Staphylococcus aureus S1 of about ∼30 %. Interestingly, genes thought to be involved in the virulence of MRSA-S1, like nuc and pvl which code, respectively, for nuclease and Panton-Valentine leucocidin, were shown to be downregulated following treatment with EntDD14 and methicillin. Similar effects were registered for other genes such as cflA, cflB and icaB, coding for bacterial ligands clumping factors A, B and intercellular adhesion factor respectively. All these data, suggest that combinations of bacteriocins and antibiotics are useful as a backup for treatment of bacterial infections.
Topics: Bridged-Ring Compounds; Drug Resistance, Bacterial; Drug Synergism; Methicillin; Methicillin-Resistant Staphylococcus aureus
PubMed: 34521050
DOI: 10.1016/j.micres.2021.126864 -
Mikrobiyoloji Bulteni Jan 2022Inappropriate and uncontrolled use of antibiotics in humans and animals leads to the emergence of multi-resistant bacteria. Before the discovery of antibiotics, plant...
Inappropriate and uncontrolled use of antibiotics in humans and animals leads to the emergence of multi-resistant bacteria. Before the discovery of antibiotics, plant extracts and essential oils were used for therapeutic purposes. Today, due to increasing antibiotic resistance, many studies are frequently carried out on the antimicrobial activities of natural active substances that can be a source for new drug candidates. The aim of this study was to investigate the antibacterial activity of components such as α-pinene (α-PN), p-cymene (p-CYM), carvacrol (CAR), thymol (TY) and eugenol (EG) found in the essential oils of many plants and their synergistic interaction with antibiotics. In this study, the antibacterial activity of these essential oil components and antibiotics in clinical use such as gentamicin (GEN), tetracycline (TET), tigecycline (TGC) and linezolid (LZD), against Staphylococcus aureus [methicillin resistant S.aureus (MRSA), and methicillin sensitive S.aureus (MSSA)], Escherichia coli and Pseudomonas aeruginosa strains were determined by disc diffusion and microdilution method. In addition, the interaction between the essential oil components and antibiotics was also determined by the checkerboard method. While CAR, TY and EG components showed strong antibacterial activity, the antibacterial activity of αPN and p-CYM was found to be weak. Combinations of α-pinene, carvacrol, thymol and eugenol with gentamicin and tetracycline mostly showed synergistic interactions against all bacteria. In αPN, CAR, TY and EG with GEN and TET, synergistic/partial synergistic interaction was observed against S.aureus strains, while indifferent interaction was detected in E.coli and P.aeruginosa strains. The combination of αPN and p-CYM with TGC showed synergistic interaction against E.coli and P.aeruginosa strains, and additive and indifferent interaction against S.aureus strains. On the other hand, synergistic interaction was observed against all bacterial strains in combinations of TGC and CAR, TY and EG components. Antagonistic interaction was not detected in any of the tested component-antibiotic combinations against the bacteria used in our study. A synergistic interaction between natural bioactive components and commonly used antibiotics may contribute to the effectiveness of antibiotics and components at lower doses, minimizing their potential toxic side effects and reducing treatment costs. However, more research is needed in terms of their pharmacokinetic and toxic properties to evaluate the therapeutic application potential of phytochemicals.
Topics: Animals; Anti-Bacterial Agents; Drug Synergism; Humans; Methicillin; Microbial Sensitivity Tests; Oils, Volatile
PubMed: 35088963
DOI: 10.5578/mb.20229908 -
Frontiers in Cellular and Infection... 2022The formation of a biofilm on the implant surface is a major cause of intractable implant-associated infection. To investigate the antibiotic concentration needed to...
The formation of a biofilm on the implant surface is a major cause of intractable implant-associated infection. To investigate the antibiotic concentration needed to eradicate the bacteria inside a biofilm, the minimum biofilm eradication concentration (MBEC) has been used, mostly against biofilms on plastic surfaces. To produce a more clinically relevant environment, an MBEC assay against biofilms on stainless-steel implants formed in a rat femoral infection model was developed. The rats were implanted with stainless steel screws contaminated by two strains (UAMS-1, methicillin-sensitive ; USA300LAC, methicillin-resistant ) and euthanized on days 3 and 14. Implants were harvested, washed, and incubated with various concentrations (64-4096 μg/mL) of gentamicin (GM), vancomycin (VA), or cefazolin (CZ) with or without an accompanying systemic treatment dose of VA (20 μg/mL) or rifampicin (RF) (1.5 μg/mL) for 24 h. The implant was vortexed and sonicated, the biofilm was removed, and the implant was re-incubated to determine bacterial recovery. MBEC on the removed biofilm and implant was defined as MBEC and implant MBEC, respectively, and the concentrations of 100% and 60% eradication were defined as MBEC and MBEC, respectively. As for MBEC, MBEC of GM was 256-1024 μg/mL, but that of VA and CZ ranged from 2048-4096 μg/mL. Surprisingly, the implant MBEC was much higher, ranging from 2048 μg/mL to more than 4096 μg/mL. The addition of RF, not VA, as a secondary antibiotic was effective, and MBEC on day 3 USA300LAC biofilm was reduced from 1024 μg/mL with GM alone to 128 μg/mL in combination with RF and the MBEC on day 14 USA300LAC biofilm was reduced from 2048 μg/mL in GM alone to 256 μg/mL in combination with RF. In conclusion, a novel MBEC assay for biofilms on orthopedic implants was developed. GM was the most effective against both methicillin-sensitive and methicillin-resistant , in biofilms, and the addition of a systemic concentration of RF reduced MBEC of GM. Early initiation of treatment is desired because the required concentration of antibiotics increases with biofilm maturation.
Topics: Animals; Anti-Bacterial Agents; Biofilms; Gentamicins; Methicillin; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Rats; Rifampin; Rodentia; Vancomycin
PubMed: 35846761
DOI: 10.3389/fcimb.2022.896978 -
Journal of Orthopaedic Surgery (Hong... 2022To determine mortality and outcomes of patients diagnosed with fracture-related infections (FRIs). FRI patients treated at a trauma centre between 2001 and 2020 were... (Review)
Review
To determine mortality and outcomes of patients diagnosed with fracture-related infections (FRIs). FRI patients treated at a trauma centre between 2001 and 2020 were analysed. The primary outcome was 1-year mortality; mortality associations with FRI organism, depth of involvement, and temporality were investigated with multivariable survival analysis. Healthcare-associated and serological outcomes were reported as secondary outcomes. 311 FRIs with mean age of 67.0 and median Charlson comorbidity index of 0 were analysed. Methicillin-sensitive (MSSA) (29.9%) was the most frequently implicated organism. The majority of FRIs were deep infections (62.7%). FRIs were diagnosed at a median of 40 (IQR 15-200) days post index surgery. The mean follow-up was 5.9 years. One-year mortality amounted to 17.7%. MSSA FRIs were associated with better survival (adj HR 0.34, 95%CI 0.15-0.76, = 0.008). There was no difference in survivorship between deep or superficial FRI (adj HR 0.86, 95%CI 0.62-1.19, = 0.353) or in relation to onset time (adj HR 1.0, 95%CI 0.99-1.00, = 0.943). Implant removal or debridement alone was performed in 61.7% and 17% respectively. Antibiotics was prescribed for 53 (IQR 23-110) days, and patients were hospitalised for 39 (IQR 19-78) days. CRP and ESR normalised in 70.3% (median 46 days) and 53.8% (median 86 days) patients respectively. Fracture-related infections are associated with significant mortality and morbidity regardless of depth and temporality. Non-MSSA FRIs are associated with inferior survival.
Topics: Humans; Aged; Fractures, Bone; Staphylococcus aureus; Staphylococcal Infections; Methicillin; Anti-Bacterial Agents; Retrospective Studies
PubMed: 36545946
DOI: 10.1177/10225536221118519 -
The Korean Journal of Internal Medicine Jan 2019
Topics: Bacteremia; Humans; Methicillin; Methicillin-Resistant Staphylococcus aureus; Staphylococcal Infections
PubMed: 30612420
DOI: 10.3904/kjim.2018.435