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Moist Environment (moist + environment)
Selected AbstractsTopical silver-impregnated dressings and the importance of the dressing technologyINTERNATIONAL WOUND JOURNAL, Issue 5 2009Keith Cutting ABSTRACT A wide variety of silver-impregnated wound dressings has become available in recent years. This has given the practitioner choice but little evidence by which an appropriate dressing may be selected. In many instances, the ancillary function(s) of the dressing will become differentiating factors that influence choice. For example, the dressing capacity to manage exudate, maintain an optimum moist environment, reduce or avoid maceration, maintain an intimate contact with the wound bed, promote autolytic debridement, sequester bacteria and bind matrix metallo proteases (MMPs) are some of those functions that are of clinical significance and may dictate choice. In this article we present the evidence for these functions, thereby enabling practitioners to evaluate comparative dressing attributes, and so make an informed choice of which silver dressing best suits the needs of the wound under differing circumstances. [source] Tissue reactions to sutures in the presence and absence of anti-infective therapyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2005Knut N. Leknes Abstract Background: In the oral cavity, sutures are placed within tissues of high vascularity in a moist environment with infectious potential. The objective of this study was to evaluate tissue reactions at silk and expanded polytetrafluoroethylene (ePTFE) sutures in the presence and absence of anti-infective therapy (AT). Methods: Thirty-six sutures were placed within the mandibular keratinized gingiva in six Beagle dogs. Each animal received one braided silk (4-0) and one ePTFE (CV-5) suture in contra-lateral jaw quadrants at 14, 7, and 3 days prior to biopsy. Three animals received daily AT including topical 2% chlorhexidine solution and a systemic broad-spectrum antibiotic. Biopsy specimens allowed histometric analysis of tissue reactions along the central part of the suture loop including the area of perisutural epithelium, ratio inflammatory cells (ICs)/epithelial cells and IC/fibroblasts, and presence/absence of bacterial plaque in the suture track. Results: A perisutural epithelial sheath was forming within 3 days. The cross-sectional area of the epithelium increased with time for both suture materials (p=0.003) but was particularly pronounced for the silk sutures in the absence of AT. Clusters of IC were present in the perisutural connective tissue and epithelium. Over time, a more prominent increase in IC/fibroblasts was evident for the silk sutures in the absence of AT. The pooled material revealed a significantly higher IC/fibroblast ratio for silk compared with ePTFE sutures (p=0.017). Bacterial plaque influx was detected in 6/9 silk and 0/9 ePTFE suture channels in the presence, and 6/6 and 3/6 suture channels, respectively, in the absence of AT. Conclusions: AT may reduce biofilm formation and inflammation along the suture track. Braided silk, however, elicits more severe tissue reactions than ePTFE regardless of infection control. [source] Influence of Moisture on Ultra-High-Temperature Tensile Creep Behavior of in Situ Single-Crystal Oxide Ceramic Alumina/Yttrium Aluminum Garnet Eutectic CompositeJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2003Yoshihisa Harada Tensile creep tests were conducted for an in situ single-crystal alumina/yttrium aluminum garnet (Al2O3/Y3Al5O12 (YAG)) binary system eutectic composite at temperatures between 1773 and 1873 K in air and in a moist environment having a water-vapor pressure range of 0.06,0.6 MPa, under a constant tensile stress range of 100,160 MPa. The Al2O3/YAG eutectic composite exhibited a stress exponent of 8,13, indicative of tensile creep behavior characterized by a dislocation back-stress mechanism. Water-vapor pressures ,0.4 MPa led to a significant acceleration of creep rates as a result of enhanced dislocation mobility in the Al2O3 and YAG phases. [source] Survival of Escherichia coli O157 in faeces of experimentally infected rats and domestic pigeonsLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2000In order to evaluate the role of some synanthropic animals in the spreading of Escherichia coli O157, laboratory rats and domestic pigeons were experimentally infected per os with E. coli O157. Rats infected with 105 colony forming units (cfu) (n = 5) and 109 cfu (n = 5) shed E. coli O157 for 2 ± 1·7 d and 9·8 ± 1·3 d, respectively. In the faeces of infected rats stored at 4 °C in a moist environment, at 4 °C in a dry environment or at 20 °C in a moist environment, E. coli O157 survived for 34 weeks. When stored at 20 °C or ,,20 °C in a dry environment, E. coli O157 survived for , 36 weeks. Pigeons infected with 105 cfu (n = 5) and 109 cfu (n = 5) shed the pathogen for 14·8 ± 3·4 d and 20·2 ± 5·2 d, respectively. Both species, rats and pigeons can be important in spreading of the E. coli O157 infection in cattle. [source] Conditioning period, CO2 and GR24 influence ethylene biosynthesis and germination of Striga hermonthicaPHYSIOLOGIA PLANTARUM, Issue 1 2000Abdel Gabbar T. Babiker Germination of witchweed (Striga hermonthica [Del.] Benth), an important root parasite on poaceous crops, requires pretreatment ,conditioning' in a warm moist environment and a subsequent exposure to a stimulant. The roles of conditioning period, CO2 and a strigol analogue (GR24) in ethylene biosynthesis and germination of the parasite were investigated. Conditioning increased the seeds' capacity to oxidize exogenous 1-aminocyclopropane-1-carboxylic acid (ACC). Exogenous CO2 increased the seeds capacity to oxidize ACC by 3- to 9-fold. A combination of GR24 and ACC increased ethylene production by more than 3-fold in comparison with the rates obtained using these compounds separately. Aminoethoxyvinylglycine (AVG) completely inhibited ethylene induction by GR24, but not by ACC. A GR24 treatment, made subsequent to conditioning in GR24, did not induce ethylene. However, seeds conditioned in GR24 and then given 1 mM ACC produced 293 nl l,1 ethylene. ACC oxidase (ACCO) activity in crude extracts was increased by conditioning and CO2. The enzyme displayed an absolute requirement for ascorbate. Absence of exogenous Fe2+ reduced enzyme activity only by 14%. GR24 applied during conditioning reduced germination in response to a subsequent GR24 treatment. ACC was, invariably, less effective in inducing S. hermonthica germination than GR24 even at concentrations which induce more ethylene than concurrent GR24 treatments. The results are consistent with a model in which conditioning removes a restriction on the ethylene biosynthetic pathway in S. hermonthica seeds. GR24 modulates the key enzymes in ethylene biosynthesis. The stimulant suppresses ethylene biosynthesis in unconditioned seeds and promotes it in conditioned ones. Germination of S. hermonthica results from the joint action of GR24 and the ethylene it induces. [source] Antibacterial Activity of an Atmospheric Pressure Plasma Jet Against Relevant Wound Pathogens in vitro on a Simulated Wound EnvironmentPLASMA PROCESSES AND POLYMERS, Issue 3-4 2010Georg Daeschlein Abstract The aim of the study was to test the efficacy of a hand-held atmospheric pressure plasma jet (APPJ) toward typical wound pathogens in vitro simulating antisepsis on wound surfaces. The plasma jet has been proved to be highly effective in vitro against the most commonly encountered pathogenic species of acute and chronic wounds reaching nearly the power of antiseptics. The following bacteria and fungi were treated on half rigid media (agar) imitating wound colonization: methicillin-sensitive Staphylococcus aureus ATCC 1924 (MSSA), Enterococcus faecium ATCC 6057 (EF), Pseudomonas aeruginosa ATCC 15442 (PA), Candida albicans ATCC 10231 (CA), and , -hemolyzing Streptococci of the Lancefield serogroup A (HSA). Highest reduction factor (RF) was obtained treating PA (RF 4.0) followed by HSA (3.2), MSSA (2.7), CA (2.0), and EF (1.9). Consequently, simulating wound surfaces with moist environment using semisolid agar media, the APPJ allowed bactericidal treatment of highly contaminated surfaces of 55,cm2 imitating skin and wound colonization within 6,min. This antibacterial reduction power together with its handsome flexibility of the APPJ could be a suited therapeutic option in the therapy of infected or colonized wounds. [source] Canal Wall Reconstruction with Mimix Hydroxyapatite Cement: Results in an Animal Model and Case Study,THE LARYNGOSCOPE, Issue 12 2003John Dornhoffer MD Abstract Objective/Hypothesis To assess Mimix hydroxyapatite cement for its applicability in canal wall reconstruction using the gerbil as a canal wall model. A case is presented to illustrate a novel technique of canal wall reconstruction using Mimix on the basis of the findings of our animal research. Study Design This was a preclinical study. Methods Ten Mongolian gerbils were implanted with Mimix, with the left side used to simulate mastoid obliteration and the right side used to simulate canal wall reconstruction. Pre- and postsurgery auditory-evoked brainstem responses were used to assess ototoxicity, and hematoxylin-eosin staining of histologic sections was used to assess inflammatory and foreign-body response and new bone formation. Results Rapid wound healing was achieved with each of the nine animals evaluated, with no erythema, edema, or drainage. Inspection of the ear canal at the time of sacrifice revealed no signs of otitis media and no middle ear effusions. Microscopic examination showed no inflammatory response or foreign-body reaction, good mucosalization on the side of the implant facing the bulla, and minimal fibrosis adjacent to the skin. Eight of nine specimens showed new woven bone ingrowth at the bone implant interface, with active osteoblasts and viable lacunae cells. There were no apparent fractures in the implanted material. Conclusions Mimix hydroxyapatite cement is biocompatible and suitable for canal wall reconstruction in the animal model. The characteristics of this cement, namely its ability to set quickly in a moist environment, offer advantages over previously used cements for canal wall reconstruction. [source] | ||||||||||||||||