Antimicrobial effects of a new brushing solution concept on a multispecies in vitro biofilm model growing on titanium surfaces.

Background—the graphene-doping procedure represents a useful procedure to improve the mechanical, physical and biological response of several Polymethyl methacrylate (PMMA)-derived polymers and biomaterials for dental applications. The aim of this study was to evaluate osseointegration of Graphene doped Poly(methyl methacrylate) (GD-PMMA) compared with PMMA as potential materials for dental implant devices. Methods—eighteen adult New Zealand white male rabbits with a mean weight of approx. 3000 g were used in this research. A total of eighteen implants of 3.5 mm diameter and 11 mm length in GD-PMMA and eighteen implants in PMMA were used. The implants were placed into the articular femoral knee joint. The animals were sacrificed after 15, 30 and 60 days and the specimens were evaluated by µCT and histomorphometry. Results—microscopically, all 36 implants, 18 in PMMA and 18 in DG-PMMA were well-integrated into the bone. The implants were in contact with cortical bone along the upper threads, while the lower threads were in contact with either newly formed bone or with marrow spaces. The histomorphometry and µCT evaluation showed that the GP-PMMA and PMMA implants were well osseointegrated and the bone was in direct contact with large portions of the implant surfaces, including the space in the medullary canal. Conclusions—in conclusion, the results suggest that GD-PMMA titanium surfaces enhance osseointegration in rabbit femurs. This encourages further research to obtain GD-PMMA with a greater radiopacity. Also, further in vitro and vivo animal studies are necessary to evaluate a potential clinical usage for dental implant applications.

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In Vitro Anti-Biofilm and Antibacterial Properties of Streptococcus downii sp. nov.

Microorganisms ◽

10.3390/microorganisms9020450 ◽

2021 ◽

Vol 9 (2) ◽

pp. 450

Author(s):

Maigualida Cuenca ◽

María Carmen Sánchez ◽

Pedro Diz ◽

Lucía Martínez-Lamas ◽

Maximiliano Álvarez ◽

...

Keyword(s):

Antibacterial Activity ◽

Quantitative Polymerase Chain Reaction ◽

Bacterial Load ◽

Antibacterial Properties ◽

Antibacterial Activities ◽

Oral Bacteria ◽

Periodontal Pathogens ◽

Biofilm Model ◽

Biofilm Development

The aim of this study was to evaluate the potential anti-biofilm and antibacterial activities of Streptococcus downii sp. nov. To test anti-biofilm properties, Streptococcus mutans, Actinomyces naeslundii, Veillonella parvula, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans were grown in a biofilm model in the presence or not of S. downii sp. nov. for up to 120 h. For the potential antibacterial activity, 24 h-biofilms were exposed to S. downii sp. nov for 24 and 48 h. Biofilms structures and bacterial viability were studied by microscopy, and the effect in bacterial load by quantitative polymerase chain reaction. A generalized linear model was constructed, and results were considered as statistically significant at p < 0.05. The presence of S. downii sp. nov. during biofilm development did not affect the structure of the community, but an anti-biofilm effect against S. mutans was observed (p < 0.001, after 96 and 120 h). For antibacterial activity, after 24 h of exposure to S. downii sp. nov., counts of S. mutans (p = 0.019) and A. actinomycetemcomitans (p = 0.020) were significantly reduced in well-structured biofilms. Although moderate, anti-biofilm and antibacterial activities of S. downii sp. nov. against oral bacteria, including some periodontal pathogens, were demonstrated in an in vitro biofilm model.

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Strong Antimicrobial and Healing Effects of Beta-Acids from Hops in Methicillin-Resistant Staphylococcus aureus-Infected External Wounds In Vivo

Antibiotics ◽

10.3390/antibiotics10060708 ◽

2021 ◽

Vol 10 (6) ◽

pp. 708

Author(s):

Radek Sleha ◽

Vera Radochova ◽

Jiri Malis ◽

Alexander Mikyska ◽

Milan Houska ◽

...

Keyword(s):

Wound Healing ◽

Porcine Model ◽

Therapeutic Effects ◽

Methicillin Resistant ◽

Antimicrobial Effects ◽

Therapeutic Modalities ◽

Positive Effects ◽

Inflammatory Parameters

Staphylococcus (S.) aureus is an important causative agent of wound infections with increasing incidence in the past decades. Specifically, the emergence of methicillin-resistant S. aureus (MRSA) causes serious problems, especially in nosocomial infections. Therefore, there is an urgent need to develop of alternative or supportive antimicrobial therapeutic modalities to meet these challenges. Purified compounds from hops have previously shown promising antimicrobial effects against MRSA isolates in vitro. In this study, purified beta-acids from hops were tested for their potential antimicrobial and healing properties using a porcine model of wounds infected by MRSA. The results show highly significant antimicrobial effects of the active substance in both the powder and Ambiderman-based application forms compared to both no-treatment control and treatment with Framycoin. Moreover, the macroscopic evaluation of the wounds during the treatment using the standardized Wound Healing Continuum indicated positive effects of the beta-acids on the overall wound healing. This is further supported by the microscopic data, which showed a clear improvement of the inflammatory parameters in the wounds treated by beta-acids. Thus, using the porcine model, we demonstrate significant therapeutic effects of hops compounds in the management of wounds infected by MRSA. Beta-acids from hops, therefore, represent a suitable candidate for the treatment of non-responsive nosocomial tissue infections by MRSA.

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Pectin limits epithelial barrier disruption by Citrobacter rodentium through anti-microbial effects

Food & Function ◽

10.1039/d0fo02605k ◽

2021 ◽

Author(s):

M. Beukema ◽

K. Ishisono ◽

J. de Waard ◽

M. M. Faas ◽

P. de Vos ◽

...

Keyword(s):

Epithelial Cells ◽

Epithelial Barrier ◽

Citrobacter Rodentium ◽

Barrier Dysfunction ◽

Antimicrobial Effects ◽

Barrier Disruption ◽

Microbial Effects

Pectins inhibit the growth of C. rodentium in vitro, preventing attachment of C. rodentium to CMT93 epithelial cells. Through these antimicrobial effects, pectins protect the epithelium from C. rodentium-induced barrier dysfunction and damage.

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Long-lasting renewable antibacterial porous polymeric coatings enable titanium biomaterials to prevent and treat peri-implant infection

Nature Communications ◽

10.1038/s41467-021-23069-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Shuyi Wu ◽

Jianmeng Xu ◽

Leiyan Zou ◽

Shulu Luo ◽

Run Yao ◽

...

Keyword(s):

Dental Implant ◽

Pathogenic Bacteria ◽

Titanium Surface ◽

Polymeric Coating ◽

Antibacterial Efficacy ◽

Polymeric Coatings ◽

Implant Infection ◽

Titanium Surfaces

AbstractPeri-implant infection is one of the biggest threats to the success of dental implant. Existing coatings on titanium surfaces exhibit rapid decrease in antibacterial efficacy, which is difficult to promisingly prevent peri-implant infection. Herein, we report an N-halamine polymeric coating on titanium surface that simultaneously has long-lasting renewable antibacterial efficacy with good stability and biocompatibility. Our coating is powerfully biocidal against both main pathogenic bacteria of peri-implant infection and complex bacteria from peri-implantitis patients. More importantly, its antibacterial efficacy can persist for a long term (e.g., 12~16 weeks) in vitro, in animal model, and even in human oral cavity, which generally covers the whole formation process of osseointegrated interface. Furthermore, after consumption, it can regain its antibacterial ability by facile rechlorination, highlighting a valuable concept of renewable antibacterial coating in dental implant. These findings indicate an appealing application prospect for prevention and treatment of peri-implant infection.

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