scholarly journals Gut microbiota, body weight and histopathological examinations in experimental infection by methicillin-resistant Staphylococcus aureus: antibiotic versus bacteriocin

2021 ◽  
pp. 1-12
Author(s):  
K. Bendjeddou ◽  
S. Hamma-Faradji ◽  
A. Ait Meddour ◽  
Y. Belguesmia ◽  
B. Cudennec ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Body Weight ◽  
Gut Microbiota ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Soft Tissues ◽  
Methicillin Resistant ◽  
Antimicrobial Drug Resistance ◽  
Histopathological Alterations ◽  
Genus Richness

Bacteriocins have been steadily reported as potential agents that may contribute, in different ways, to overcome antimicrobial drug resistance. Here, holoxenic NMRI-F mice microbiota, their body weight recovery and histopathological alterations of organs like colon, spleen and liver were examined in mice intraperitoneally infected with 108 cfu of a clinical methicillin-resistant Staphylococcus aureus (MRSA-1), and treated with enterocin DD14 alone (165 mg/kg), erythromycin alone (100 mg/kg) or their combination. Animals that received both antimicrobials presented a better body weight recovery than other groups. Less pronounced histopathological alterations were observed in mice MRSA-infected and treated with bacteriocin than in those MRSA-infected but untreated or MRSA-infected and treated with erythromycin. Noteworthy, these alterations were absent when mice were treated with MRSA-infected and treated with both antibacterial agents. Furthermore, the genus richness was significantly lower in mice infected and treated with erythromycin, compared to mice infected and treated with both antimicrobials. The beta-diversity analysis showed that non-infected mice and those infected and treated with both antimicrobials, stand apart from the other groups as supported in a NMDS model. This in vivo study shows the relevance of bacteriocin, or bacteriocin-antibiotic formulation in protecting colonic, liver and spleen soft tissues and controlling the mouse gut microbiota, following MRSA infection.

scholarly journals Efficacy of LY333328 against Experimental Methicillin-Resistant Staphylococcus aureus Endocarditis

1998 ◽  
Vol 42 (4) ◽  
pp. 981-983 ◽  
Author(s):  
Glenn W. Kaatz ◽  
Susan M. Seo ◽  
Jeffrey R. Aeschlimann ◽  
Heather H. Houlihan ◽  
Renee-Claude Mercier ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Body Weight ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Rabbit Model ◽  
Glycopeptide Antibiotic ◽  
In Vivo Efficacy ◽  
Methicillin Resistant ◽  
Therapeutic Alternative ◽  
Staphylococcus Aureus Endocarditis

ABSTRACT The in vivo efficacy of LY333328, a new glycopeptide antibiotic, was compared with that of vancomycin by using the rabbit model of left-sided methicillin-resistant Staphylococcus aureusendocarditis. Animals received LY333328 or vancomycin (25 mg/kg of body weight every 24 or 8 h, respectively) for 4 days. These drugs were equally effective in clearing bacteremia and in reducing bacterial counts in vegetations and tissues. We conclude that in this model, LY333328 was microbiologically effective and may be a therapeutic alternative to vancomycin.

scholarly journals Importance of penicillinase production for activity of penicillin alone or in combination with sulbactam in experimental endocarditis due to methicillin-resistant Staphylococcus aureus.

1996 ◽  
Vol 40 (5) ◽  
pp. 1219-1224 ◽  
Author(s):  
B Fantin ◽  
J Pierre ◽  
N Castéla-Papin ◽  
L Saint-Julien ◽  
H Drugeon ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Body Weight ◽  
Synergistic Effect ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methicillin Resistance ◽  
Limiting Factor ◽  
High Dose ◽  
Methicillin Resistant

The activity of penicillin, alone and in combination with sulbactam, against a heterogeneously methicillin-resistant, penicillinase-producing clinical isolate of Staphylococcus aureus and its penicillinase-negative derivative was investigated in vitro and in a rabbit experimental endocarditis model. Penicillin was significantly more effective than vancomycin against the penicillinase-negative derivative in vivo (P < 0.001), and it sterilized 25% of the vegetations. The combination of penicillin and sulbactam exhibited an in vivo synergistic effect on the penicillinase-producing strain (P < 0.01) but did not produce any advantage over treatment with vancomycin, even when a high dose of sulbactam was used (100 mg/kg of body weight every 6 h). This combination was significantly less effective against the penicillinase-producing strain than was penicillin alone against the penicillinase-negative derivative (P < 0.03). In addition, the most resistant subpopulation of the surviving bacteria, which grew on agar containing 16 micrograms of methicillin per ml, was detected in 5 of 6 animals treated with penicillin and a high dose of sulbactam against the penicillinase-producing strain compared with only 1 of 12 animals treated with penicillin alone against the penicillinase-negative derivative (P < 0.01). We conclude that penicillin is highly effective against penicillinase-negative methicillin-resistant S. aureus and that penicillinase production, rather than methicillin resistance, appears to be the limiting factor for the activity of the penicillin-sulbactam combination against penicillinase-producing, methicillin-resistant S. aureus.

Severe Sepsis Attributable to Community-Associated Methicillin-Resistant Staphylococcus aureus: An Emerging Fatal Problem

2007 ◽  
Vol 73 (7) ◽  
pp. 684-687 ◽  
Author(s):  
Eric T. Castaldo ◽  
Edmund Y. Yang
Keyword(s):  
Staphylococcus Aureus ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Soft Tissues ◽  
Hospital Admissions ◽  
Primary Source ◽  
Necrotizing Pneumonia ◽  
Inclusion Criteria ◽  
Methicillin Resistant ◽  
Cardiorespiratory Failure ◽  
Source Of Infection

We observed a number of cases of sepsis from bacteremia in children from community-associated methicillin-resistant Staphylococcus aureus (MRSA), which led us to study its patterns of infection and outcome. A retrospective review identifying children admitted to our institution with blood culture-proven community-associated MRSA sepsis over a 2-year period was performed. The inclusion criteria were younger than 19 years old, two or more blood cultures for MRSA within 48 hours of admission, evidence of systemic inflammatory response syndrome, and no prior hospital admissions within 6 months. Eight patients were included; seven required mechanical ventilation. Vasopressors were required in seven patients. Four patients required extra-corporeal membrane oxygenation. Four patients had culture-proven septic arthritis or thrombophlebitis and three of these patients developed bilateral necrotizing pneumonia. Bilateral necrotizing pneumonia was identified in the other four patients, but the primary source of infection was never identified. The overall intact neurologic survival was 50 per cent. Children with severe community-associated MRSA sepsis can rapidly progress to cardiorespiratory failure. Mortality appears to be high, and children may benefit from a search of their soft tissues and joints to identify the source of infection to prevent embolic dissemination.

scholarly journals Group V Phospholipase A2 Mediates Endothelial Dysfunction and Acute Lung Injury Caused by Methicillin-Resistant Staphylococcus aureus

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1731
Author(s):  
Yu Maw Htwe ◽  
Huashan Wang ◽  
Patrick Belvitch ◽  
Lucille Meliton ◽  
Mounica Bandela ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Acute Lung Injury ◽  
Endothelial Dysfunction ◽  
Lung Injury ◽  
Phospholipase A2 ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Group V ◽  
Methicillin Resistant

Lung endothelial dysfunction is a key feature of acute lung injury (ALI) and clinical acute respiratory distress syndrome (ARDS). Previous studies have identified the lipid-generating enzyme, group V phospholipase A2 (gVPLA2), as a mediator of lung endothelial barrier disruption and inflammation. The current study aimed to determine the role of gVPLA2 in mediating lung endothelial responses to methicillin-resistant Staphylococcus aureus (MRSA, USA300 strain), a major cause of ALI/ARDS. In vitro studies assessed the effects of gVPLA2 inhibition on lung endothelial cell (EC) permeability after exposure to heat-killed (HK) MRSA. In vivo studies assessed the effects of intratracheal live or HK-MRSA on multiple indices of ALI in wild-type (WT) and gVPLA2-deficient (KO) mice. In vitro, HK-MRSA increased gVPLA2 expression and permeability in human lung EC. Inhibition of gVPLA2 with either the PLA2 inhibitor, LY311727, or with a specific monoclonal antibody, attenuated the barrier disruption caused by HK-MRSA. LY311727 also reduced HK-MRSA-induced permeability in mouse lung EC isolated from WT but not gVPLA2-KO mice. In vivo, live MRSA caused significantly less ALI in gVPLA2 KO mice compared to WT, findings confirmed by intravital microscopy assessment in HK-MRSA-treated mice. After targeted delivery of gVPLA2 plasmid to lung endothelium using ACE antibody-conjugated liposomes, MRSA-induced ALI was significantly increased in gVPLA2-KO mice, indicating that lung endothelial expression of gVPLA2 is critical in vivo. In summary, these results demonstrate an important role for gVPLA2 in mediating MRSA-induced lung EC permeability and ALI. Thus, gVPLA2 may represent a novel therapeutic target in ALI/ARDS caused by bacterial infection.

Recurrent Methicillin-Resistant Staphylococcus Aureus Osteomyelitis: Combination Antibiotic Therapy with Evaluation by Serum Bactericidal Titers

1995 ◽  
Vol 29 (7-8) ◽  
pp. 694-697 ◽  
Author(s):  
Sherrie L Aspinall ◽  
David M Friedland ◽  
Victor L Yu ◽  
John D Rihs ◽  
Robert R Muder
Keyword(s):  
Staphylococcus Aureus ◽  
Back Pain ◽  
Antibiotic Therapy ◽  
Sedimentation Rate ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Blood Cultures ◽  
Low Back ◽  
Methicillin Resistant ◽  
Trough Concentrations

Objective: To report on a patient with recurrent methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis and bacteremia successfully treated with combination antibiotic therapy. Case Summary: Two sets of blood cultures from a 55-year-old man with fever, malaise, and low back pain grew MRSA. Radiologic studies of the spine showed bony changes consistent with osteomyelitis. Soon after completing 6 weeks of vancomycin, the patient experienced a recurrence of back pain. Laboratory values included an increase in the sedimentation rate to 53 mm/h and positive blood cultures for MRSA. Vancomycin, gentamicin, and rifampin were administered for 8 weeks. Serum inhibitory and bactericidal titers were more than 1:1024 for both the peak and trough concentrations. Radiologic studies of the spine showed healing osteomyelitis. Two years after completion of antibiotic therapy, the infection has not recurred. Discussion: Antibiotic therapy alone was attempted because the patient was considered a risky surgical candidate. Serum inhibitory and bactericidal titers documented the high in vivo activity of the vancomycin, gentamicin, and rifampin combination. Initiation of vancomycin therapy led to disappearance of the fever and back pain. Cure was documented by sustained normalization of the erythrocyte sedimentation rate and radiologic evidence of healing. Conclusions: Combination antibiotic therapy with vancomycin, rifampin, and low-dose gentamicin (1 mg/kg q12h) may be useful for deep-seated tissue infection caused by MRSA.

scholarly journals A Novel Dicationic Boron Dipyrromethene-based Photosensitizer for Antimicrobial Photodynamic Therapy against Methicillin-Resistant Staphylococcus aureus

2020 ◽  
Vol 28 ◽  
Author(s):  
Priyanga Dharmaratne ◽  
Ligang Yu ◽  
Roy Chi-Hang Wong ◽  
Ben Chun-Lap Chan ◽  
Kit-Man Lau ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Photodynamic Therapy ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Skin Irritation ◽  
Scientific Basis ◽  
Positive Control ◽  
Methicillin Resistant ◽  
Boron Dipyrromethene ◽  
Mrsa Strains

Background: We report herein the synthesis of a novel dicationic boron dipyrromethene derivative (compound 3) which is symmetrically substituted with two trimethylammonium styryl groups. Methods: The antibacterial photodynamic activity of compound 3 was determined against sixteen methicillin-resistant Staphylococcus aureus (MRSA) strains, including four ATCC type strains (ATCC 43300, ATCC BAA-42, ATCC BAA-43, and ATCC BAA-44), two mutant strains [AAC(6’)-APH(2”) and RN4220/pUL5054], and ten non-duplicate clinical strains of hospital- and communityassociated MRSA. Upon light irradiation, the minimum bactericidal concentrations of compound 3 were in the range of 1.56-50 µM against all the sixteen MRSA strains. Interestingly, compound 3 was not only more active than an analogue in which the ammonium groups are not directly connected to the pconjugated system (compound 4), but also showed significantly higher (p < 0.05) antibacterial potency than the clinically approved photosensitizer methylene blue. The skin irritation of compound 3 during topical application was tested on human 3-D skin constructs and proven to be non-irritant in vivo at concentrations below 1.250 mM. In the murine MRSA infected wound study, the colony forming unit reduction of compound 3 + PDT group showed significantly (p < 0.05) higher value (>2.5 log10) compared to other test groups except for the positive control. Conclusion: In conclusion, the present study provides a scientific basis for future development of compound 3 as a potent photosensitizer for photodynamic therapy for MRSA wound infection.

Sign in / Sign up

Export Citation Format

Share Document