In Vitro Analysis of the Elution of Tobramycin From a Calcium Sulfate Bone Void Filler

Bone void fillers (BVFs) containing calcium sulfate, tricalcium phosphate (TCP), and hydroxyapatite can be loaded with antibiotics for infection treatment or prevention under surgeon-directed use. The aim of this study was to characterize the handling and elution properties of a triphasic BVF loaded with common antibiotics. BVF was mixed with vancomycin and/or tobramycin to form pellets, and the set time was recorded. A partial refreshment elution study was conducted with time points at 4, 8, and 24 h, as well as 2, 7, 14, 28, and 42 days. Effects on dissolution were evaluated in a 14-day dissolution study. Set time increased to over 1 h for groups containing tobramycin, although vancomycin had a minimal effect. Pellets continued to elute antibiotics throughout the 42-day elution study, suggesting efficacy for the treatment or prevention of orthopedic infections. BVF containing vancomycin or tobramycin showed similar dissolution at 14 days compared to BVF without antibiotics; however, BVF containing both antibiotics showed significantly more dissolution.

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In Vitro Efficacy of Antibiotics Released from Calcium Sulfate Bone Void Filler Beads

Materials ◽

10.3390/ma11112265 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2265 ◽

Cited By ~ 4

Author(s):

Phillip Laycock ◽

John Cooper ◽

Robert Howlin ◽

Craig Delury ◽

Sean Aiken ◽

...

Keyword(s):

Staphylococcus Epidermidis ◽

Calcium Sulfate ◽

Joint Infection ◽

Diffusion Method ◽

Zone Of Inhibition ◽

Disk Diffusion Method ◽

Bone Void Filler ◽

Biofilm Bacteria ◽

Bone Void

15 different antibiotics were individually mixed with commercially available calcium sulfate bone void filler beads. The antibiotics were: amikacin, ceftriaxone, cefuroxime, ciprofloxacin, clindamycin, colistamethate sodium, daptomycin, gentamicin, imipenem/cilastatin, meropenem, nafcillin, rifampicin, teicoplanin, tobramycin and vancomycin. The efficacy of specific released antibiotics was validated by zone of inhibition (ZOI) testing using a modified Kirby–Bauer disk diffusion method against common periprosthetic joint infection pathogens. With a subset of experiments (daptomycin, rifampin, vancomycin alone and rifampin and vancomycin in combination), we investigated how release varied over 15 days using a repeated ZOI assay. We also tested the ability of these beads to kill biofilms formed by Staphylococcus epidermidis 35984, a prolific biofilm former. The results suggested that certain antibiotics could be combined and released from calcium sulfate with retained antibacterial efficacy. The daptomycin and rifampin plus vancomycin beads showed antimicrobial efficacy for the full 15 days of testing and vancomycin in combination with rifampin prevented resistant mutants. In the biofilm killing assay, all of the antibiotic combinations showed a significant reduction in biofilm bacteria after 24 h. The exposure time was an important factor in the amount of killing, and varied among the antibiotics.

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In Vitro Antimicrobial Activity of Calcium Sulfate and Hydroxyapatite (Cerament Bone Void Filler) Discs Using Heat-Sensitive and Non–Heat-sensitive Antibiotics Against Methicillin-Resistant Staphylococcus aureus and Pseudomonas aeruginosa

Journal of the American Podiatric Medical Association ◽

10.7547/1010146 ◽

2011 ◽

Vol 101 (2) ◽

pp. 146-152 ◽

Cited By ~ 12

Author(s):

Jeffrey C. Karr ◽

Joseph Lauretta ◽

Georgia Keriazes

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Calcium Sulfate ◽

Bone Void Filler ◽

Zones Of Inhibition ◽

Standard Set ◽

Bone Void ◽

Carrier Systems ◽

Carrier Vehicle

Background: Several absorbable and nonabsorbable antibiotic carrier systems are available in the adjunctive surgical management of osteomyelitis of the foot, ankle, and lower leg. These carrier systems have significant limitations regarding which antibiotics can be successfully incorporated into the carrier vehicle. The calcium sulfate and hydroxyapatite Cerament Bone Void Filler is a biocompatible, absorbable ceramic bone void filler that can successfully deliver multiple heat-stable and heat-unstable antibiotics that have not been generally used before with antibiotic beads in treating musculoskeletal infections. Methods: Cerament Bone Void Filler discs with the antibiotics rifampin, vancomycin, tobramycin, cefazolin, cefepime hydrochloride, vancomycin-tobramycin, piperacillin-tazobactam, ceftazidime, and ticarcillin-clavulanate were tested in vitro against methicillin-resistant Staphylococcus aureus. Results: The zones of inhibition for the Cerament Bone Void Filler antibiotic discs plated against Staphylococcus aureus obtained were 33% to 222% greater than the minimum zones of inhibition breakpoints for bacteria susceptibility as defined by the standard set by the Clinical and Laboratory Standards Institute. Cerament Bone Void Filler discs with the antibiotics plated against Pseudomonas aeruginosa produced zones of inhibition of 93% to 200% greater than the minimum zones of inhibition breakpoints for bacteria susceptibility as defined by the standard set by the Clinical and Laboratory Standards Institute. Conclusions: The calcium sulfate and hydroxyapatite Cerament Bone Void Filler was an excellent carrier vehicle for multiple antibiotics creating in vitro significant zones of inhibition, thus demonstrating susceptibility against Staphylococcus aureus and Pseudomonas aeruginosa, which holds tremendous promise in treating osteomyeilits. (J Am Podiatr Med Assoc 101(2): 146–152, 2011)

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In Vitro Activity of Calcium Sulfate and Hydroxyapatite Antifungal Disks Loaded with Amphotericin B or Voriconazole in Consideration for Adjunctive Osteomyelitis Management

Journal of the American Podiatric Medical Association ◽

10.7547/0003-0538-105.2.104 ◽

2015 ◽

Vol 105 (2) ◽

pp. 104-110 ◽

Cited By ~ 4

Author(s):

Jeffrey C. Karr ◽

Joseph Lauretta

Keyword(s):

Amphotericin B ◽

Calcium Sulfate ◽

Antifungal Drugs ◽

Adjunctive Treatment ◽

Candida Spp ◽

Bone Void Filler ◽

Zones Of Inhibition ◽

Fungal Osteomyelitis ◽

Bone Void

Background Regarding antibiotic-loaded cements, there is an abundant amount of literature regarding the antibacterial in vitro inhibitory and clinical applications for the treatment of osteomyelitis. The opposite can be said about literature regarding in vitro antifungal-loaded cement drug delivery for the treatment of fungal osteomyelitis. Methods Aspergillus fumigatus and Candida (ATCC 1023ATCC, Manassas, Virginia) were plated on antibiotic/antifungal-free plates. Voriconazole- and amphotericin B–impregnated calcium sulfate and hydroxyapatite (HA) disks, calcium sulfate + HA control disks, and control polymethylmethacrylate disks were laid separately onto plates separately inoculated with Aspergillus and Candida spp. The zones of inhibition obtained were measured in millimeters at 24, 36, and 96 hours. Results Etest (bioMérieux, Marcy l'Etoile, France) results demonstrated susceptibility of Aspergillus and Candida to amphotericin B and voriconazole. The zone of inhibition data demonstrated that voriconazole and amphotericin B retained their antifungal activity when mixed into the calcium sulfate + HA bone void filler and eluted at biologically effective antifungal concentrations over 96 hours. Conclusions The calcium sulfate + HA bone void filler is a biocompatible ceramic carrier vehicle that can successfully deliver the antifungal drugs voriconazole and amphotericin B in the adjunctive treatment of fungal osteomyelitis. It is a reliable strategy in the local delivery of antifungal drugs to an area of osteomyelitis.

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The native structure of the eukaryotic ribosome

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075890 ◽

1983 ◽

Vol 41 ◽

pp. 432-433

Author(s):

R.A. Milligan ◽

P.N.T. Unwin

Keyword(s):

Ribosomal Proteins ◽

Crystal Form ◽

Native Structure ◽

X Ray Diffraction ◽

Eukaryotic Ribosome ◽

Vitro Analysis ◽

In Vitro Analysis ◽

Resolution Structure ◽

Stable Unit

A detailed understanding of the mechanism of protein synthesis will ultimately depend on knowledge of the native structure of the ribosome. Towards this end we have investigated the low resolution structure of the eukaryotic ribosome embedded in frozen buffer, making use of a system in which the ribosomes crystallize naturally.The ribosomes in the cells of early chicken embryos form crystalline arrays when the embryos are cooled at 4°C. We have developed methods to isolate the stable unit of these arrays, the ribosome tetramer, and have determined conditions for the growth of two-dimensional crystals in vitro, Analysis of the proteins in the crystals by 2-D gel electrophoresis demonstrates the presence of all ribosomal proteins normally found in polysomes. There are in addition, four proteins which may facilitate crystallization. The crystals are built from two oppositely facing P4 layers and the predominant crystal form, accounting for >80% of the crystals, has the tetragonal space group P4212, X-ray diffraction of crystal pellets demonstrates that crystalline order extends to ~ 60Å.

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1163: Radial Dilation of Ureteral Balloons: A Comparative in-Vitro Analysis

The Journal of Urology ◽

10.1016/s0022-5347(18)35308-4 ◽

2005 ◽

Vol 173 (4S) ◽

pp. 315-316

Author(s):

Kari Hendlin ◽

Brynn Lund ◽

Manoj Monga

Keyword(s):

Vitro Analysis ◽

In Vitro Analysis

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An In Vitro Analysis of Ligament Reconstruction or Extension Osteotomy on Trapeziometacarpal Joint Stability and Contact Area

Yearbook of Hand and Upper Limb Surgery ◽

10.1016/s1551-7977(08)70357-1 ◽

2007 ◽

Vol 2007 ◽

pp. 214-215 ◽

Cited By ~ 1

Author(s):

B. Wilhelmi

Keyword(s):

Contact Area ◽

Ligament Reconstruction ◽

Joint Stability ◽

Trapeziometacarpal Joint ◽

Vitro Analysis ◽

In Vitro Analysis

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Role of the 807 C/T Polymorphism of the α2 Gene in Platelet GP Ia Collagen Receptor Expression and Function

Thrombosis and Haemostasis ◽

10.1055/s-0037-1614605 ◽

1999 ◽

Vol 81 (06) ◽

pp. 951-956 ◽

Cited By ~ 59

Author(s):

J. Corral ◽

R. González-Conejero ◽

J. Rivera ◽

F. Ortuño ◽

P. Aparicio ◽

...

Keyword(s):

Venous Thrombosis ◽

Cell Types ◽

Receptor Expression ◽

Case Control Studies ◽

Platelet Surface ◽

Vitro Analysis ◽

And Function ◽

In Vitro Analysis

SummaryThe variability of the platelet GP Ia/IIa density has been associated with the 807 C/T polymorphism (Phe 224) of the GP Ia gene in American Caucasian population. We have investigated the genotype and allelic frequencies of this polymorphism in Spanish Caucasians. The T allele was found in 35% of the 284 blood donors analyzed. We confirmed in 159 healthy subjects a significant association between the 807 C/T polymorphism and the platelet GP Ia density. The T allele correlated with high number of GP Ia molecules on platelet surface. In addition, we observed a similar association of this polymorphism with the expression of this protein in other blood cell types. The platelet responsiveness to collagen was determined by “in vitro” analysis of the platelet activation and aggregation response. We found no significant differences in these functional platelet parameters according to the 807 C/T genotype. Finally, results from 3 case/control studies involving 302 consecutive patients (101 with coronary heart disease, 104 with cerebrovascular disease and 97 with deep venous thrombosis) determined that the 807 C/T polymorphism of the GP Ia gene does not represent a risk factor for arterial or venous thrombosis.

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