Evaluation of a Diphenylphosphorylazide-Crosslinked Collagen Membrane for Guided Bone Regeneration in Mandibular Defects in Rats

in Journal of Periodontology (1998), 69(11), 1238-46

In the present study, the potential of a diphenylphosphorylazide-crosslinked type I bovine collagen membrane was evaluated in the healing of mandibular bone defects applying the biological concept of ... [more ▼]

In the present study, the potential of a diphenylphosphorylazide-crosslinked type I bovine collagen membrane was evaluated in the healing of mandibular bone defects applying the biological concept of guided bone regeneration. The experiment was carried out on 25 Wistar rats. After exposing the mandibular ramus bilaterally, 5 mm diameter full-thickness circular bone defects were surgically created. While the defect on one side was covered by the membrane (experimental), the defect on the other side was left uncovered (control) before closure of the overlying soft tissues. The rats were sacrificed in groups of 5 after 7, 15, 30, 90, and 180 days of healing. Although at early stages of healing similar amounts of bone formation were observed in the experimental and control defects, after 1 month of healing, most of the experimental defects were completely closed with new bone, while in the control defects, only limited amounts of new bone were observed at the rims and in the lingual aspect of the lesions. In the 90- and 180-day animals, all experimental defects were completely closed, while in the control defects, no statistically significant increase in bone regeneration was observed. The increase in percentage of bone regeneration in the experimental defects was statistically significant between the 15-day specimens as compared with the 7-day specimens (P < 0.01) and likewise between 30-day and 15-day specimens (P < 0.001). It can be concluded that a DPPA-crosslinked collagen membrane yields biocompatibility, ad hoc mechanical hindrance, and handling characteristics suitable for guided bone regeneration applications in this experimental model. [less ▲]

Evaluation of a geometry-based knee joint compared to a planar knee joint

in Visual Computer (2011)

Today neuromuscular simulations are used in sev- eral fields, such as diagnostics and planing of surgery, to get a deeper understanding of the musculoskeletal system. Dur- ing the last year, new models ... [more ▼]

Today neuromuscular simulations are used in sev- eral fields, such as diagnostics and planing of surgery, to get a deeper understanding of the musculoskeletal system. Dur- ing the last year, new models and datasets have been pre- sented which can provide us with more in-depth simulations and results. The same kind of development has occurred in the field of studying the human knee joint using complex three dimensional finite element models and simulations. In the field ofmusculoskeletal simulations, no such knee joints can be used. Instead themost common knee joint description is an idealized knee joint with limited accuracy or a planar knee joint which only describes the knee motion in a plane. In this paper, a new knee joint based on both equations and geometry is introduced and compared to a common clinical planar knee joint. The two kinematical models are analyzed using a gait motion, and are evaluated using the muscle ac- tivation and joint reaction forces which are compared to in- vivo measured forces. We show that we are able to predict the lateral, anterior and longitudinal moments, and that we are able to predict better knee and hip joint reaction forces. [less ▲]

Evaluation of a hydro-alcoholic solution as pre-surgical hand antisepsis in a veterinary setting.

Conference (2010, July 02)

Introduction: Despite the fact that presurgical antiseptic hand treatment of surgical staff has since become a worldwide accepted procedure, surgical site infection is still one of the most frequent types ... [more ▼]

Introduction: Despite the fact that presurgical antiseptic hand treatment of surgical staff has since become a worldwide accepted procedure, surgical site infection is still one of the most frequent types of nosocomial infections. Many products have been used for hand antisepsis, but the popularity of alcoholic rubs amongst human surgeons is increasing as they have shown to provide a rapid and immediate action, are considerably faster than disinfecting soap scrubs and cause less skin damage after repeated use. The purpose of this study was 1) to identify surgical hand antisepsis habits amongst veterinary surgery specialists in Europe (ECVS) and the United States (ACVS), 2) to compare povidone iodine and chlorhexidine gluconate scrubs with a hydro-alcoholic rub hand antisepsis protocol and 3) to evaluate the usefulness of a hydro-alcoholic rub solution in a veterinary surgical setting. Materials and Methods: Emails were sent to 1300 Diplomates to invite them to participate to an online survey in order to obtain an idea about pre-surgical hand disinfection techniques. In a preliminary trial the efficiency of 4% chlorhexidine gluconate, 7.5 % PVP-iodine and an alcoholic solution containing 45% 2-propanol, 30% 1-propanol, 0.2% mecetronium ethylsulphate (Sterillium®) in bacterial reduction on hands was compared. In a clinical trial, the suitability of Sterillium® was assessed in an equine and small animal set up during surgery procedures. Fingertips were pressed on blood agar plates and Gassner plates prior to hand antisepsis (PHA), after handantisepsis (AHA) and three hours after wearing sterile gloves (AG) in the preliminary trial or at the end of surgery (AS) in the clinical trial. Bacterial counts (colony forming units : CFU’s) were obtained after 24 h of incubation of the plates. The obtained values of CFU from PHA, AHA, AG and AS were expressed as log10 values. For each sample, a reduction factor (RF) was obtained from the difference of log10 pre-value and log10 post-value. An ANOVA comparison between the effects of the different antisepsis protocols on the mean log10 CFU values and RF’s in function of the different steps was established. Results: A 42.6% response rate was obtained for the survey. Most surgeons’ still use a disinfecting soap only (79.9%) for hand antisepsis prior to surgery, the majority based on chlorhexidine gluconate (81.4%). Significant differences were found between immediate and sustained activities of the different products tested. Sterillium® was shown to have significantly lower LSM log10 CFU at AG compared to both other products. At AHA, povidone iodine revealed to have significantly higher LSM log10 CFU than Sterillium® and chlorhexidine gluconate, with the last two products having comparable activities. Reduction factors for the Sterillium® were significantly greater than for the other products. Only RF1 was comparable between Sterillium® and chlorhexidine gluconate. In the clinical trial, no significant differences were found between surgeons regarding LSM log10 CFU after hand antisepsis, neither between RF from samples taken at the small animal versus the equine surgery theatre. Discussion: This study confirms that Sterillium® is more effective in reducing bacterial counts on hands prior to surgery in a veterinary setting as are chlorhexidine gluconate (CHX) and povidone iodine soap. Moreover, they provide better tolerance and compliance to surgical hygiene protocols. Despite this, veterinary surgeons from all over the world still prefer the use of CHX soap, which has far more disadvantages than commonly accepted. Apart from the better skin tolerance and the absence of known resitance to the product, the use of Sterillium® offers the advantage of a fast (1.5 minute) surgical handantisepsis. This study shows that, as previously reported for human medicine, Sterillium® can safely be used in a veterinary surgical setting. [less ▲]

Evaluation of a method for estimating configuration parameters in bistatic radars using directive antennas

Conference (2004)

Evaluation of a monostatic STAP-radar range-compensation method applied to selected bistatic configurations

Conference (2002, March)

Evaluation of a new biocompatible poly(N-(morpholino ethyl methacrylate)-based copolymer for the delivery of ruthenium oligonucleotides, targeting HPV16 E6 oncogene

in Journal of Biomedical Nanotechnology (2013), 9

This study investigates the use of a new biocompatible block copolymer poly(2-(dimethylamino)ethyl methacrylate-N-(morpholino)ethyl methacrylate (PDMAEMA-b-PMEMA) for the delivery of a particular ... [more ▼]

This study investigates the use of a new biocompatible block copolymer poly(2-(dimethylamino)ethyl methacrylate-N-(morpholino)ethyl methacrylate (PDMAEMA-b-PMEMA) for the delivery of a particular antisense oligonucleotide targeting E6 gene from human papilloma virus. This antisense oligonucleotide was derivatized with a polyazaaromatic RuII complex which, under visible illumination, is able to produce an irreversible crosslink with the complementary targeted sequence. The purpose of this study is to determine whether by the use of a suitable transfection agent, it is possible to increase the efficiency of the antisense oligonucleotide targeting E6 gene, named Ru-P-4. In a recent study, we showed that Oligofectamine® transfected Ru-P-4 antisense oligonucleotide failed to inhibit efficiently the growth of cervical cancer cell line SiHa, contrarily to the Ru-P-6 antisense oligonucleotide, another sequence also targeting the E6 gene. The ability of PDMAEMA-b-PMEMA to form polyplexes with optimal physicochemical characteristics was investigated first. Then the ability of the PDMAEMA-b-PMEMA/Ru-P-4 antisense oligonucleotide polyplexes to transfect two keratinocyte cell lines (SiHa and HaCat) and the capacity of polyplexes to inhibit HPV16 + cervical cancer cell growth was evaluated. PDMAEMA-b-PMEMA base polyplexes at the optimal molar ratio of polymer nitrogen atoms to DNA phosphates (N/P), were able to deliver Ru-P-4 antisense oligonucleotide and to induce a higher growth inhibition in human cervical cancer SiHa cells, compared to other formulations based on Oligofectamine®. [less ▲]

Evaluation of a new immunoassay analyzer: the photon "ERA"

Poster (1986)

Evaluation of a new immunoenzymetric assay for CK-MB (tandem-E CKMB)

in Annales de Biologie Clinique (1985), 43

Evaluation of a new laboratory high-shear mixer

Conference (1993)

Evaluation of a portable equine metabolic measurement system

in 7th International Conference on Equine Exercise Physiology (2006)