Optimization and validation of multi-coloured capillary electrophoresis for genotyping of Plasmodium falciparum merozoite surface proteins (msp1 and 2)

BACKGROUND: Genotyping of Plasmodium falciparum based on PCR amplification of the polymorphic genes encoding the merozoite surface proteins 1 and 2 (msp1 and msp2) is well established in the field of malaria research to determine the number and types of concurrent clones in an infection. Genotyping is regarded essential in anti-malarial drug trials to define treatment outcome, by distinguishing recrudescent parasites from new infections. Because of the limitations in specificity and resolution of gel electrophoresis used for fragment analysis in most genotyping assays it became necessary to improve the methodology. An alternative technique for fragment analysis is capillary electrophoresis (CE) performed using automated DNA sequencers. Here, one of the most widely-used protocols for genotyping of P. falciparum msp1 and msp2 has been adapted to the CE technique. The protocol and optimization process as well as the potentials and limitations of the technique in molecular epidemiology studies and anti-malarial drug trials are reported. METHODS: The original genotyping assay was adapted by fluorescent labeling of the msp1 and msp2 allelic type specific primers in the nested PCR and analysis of the final PCR products in a DNA sequencer. A substantial optimization of the fluorescent assay was performed. The CE method was validated using known mixtures of laboratory lines and field samples from Ghana and Tanzania, and compared to the original PCR assay with gel electrophoresis. RESULTS: The CE-based method showed high precision and reproducibility in determining fragment size (< 1 bp). More genotypes were detected in mixtures of laboratory lines and blood samples from malaria infected children, compared to gel electrophoresis. The capacity to distinguish recrudescent parasites from new infections in an anti-malarial drug trial was similar by both methods, resulting in the same outcome classification, however with more precise determination by CE. CONCLUSION: The improved resolution and reproducibility of CE in fragment sizing allows for comparison of alleles between separate runs and determination of allele frequencies in a population. The more detailed characterization of individual msp1 and msp2 genotypes may contribute to improved assessments in anti-malarial drug trials and to a further understanding of the molecular epidemiology of these polymorphic P. falciparum antigens

Contour identical implants to bridge mandibular continuity defects - individually generated by LaserCUSING® - A feasibility study in animal cadavers

Background Ablative tumor surgery often results in continuity defects of the mandible. When an immediate reconstruction using autologous bone grafts is not possible the bridging of the defects with a variety of bridging plates might be achieved. However, those bridging plates have the risk of plate fractures or exposure. Customized titanium implants manufactured using CAD/CAM and the LaserCUSING® technique might be an alternative. Methods In the present study, computed tomographies (CT) of porcine cadaver mandibles were generated and transferred into DICOM data. Following, different continuity defects were surgically created in the mandibles. Based on the DICOM data customized titanium implants were manufactured using CAD/CAM procedures and the LaserCUSING® technique. The implants were fixed to the remaining stumps with screws. Subsequently, the accuracy of the reconstructed mandibles was tested using plaster casts. Results The workflow from the CT to the application of the customized implants was proved to be practicable. Furthermore, a stable fixation of the customized implant to the remaining stumps could be achieved. The control of the accuracy showed no frictions or obstacles. Conclusion The customized titanium implant seems to be a promising approach to bridge continuity defects of the mandible whenever an immediate reconstruction with autologous bone is not possible

Prothèses totales des articulations temporomandibulaires

International audienceThe temporomandibular joint (TMJ) is probably the most complex human joint. As in all joints, its prosthetic replacement may be indicated in selected cases. Significant advances have been made in the design of TMJ prostheses during the last three decades and the indications have been clarified. The aim of our work was to make an update on the current total TMJ total joint replacement. Indications, contraindications, prosthetic components, advantages, disadvantages, reasons for failure or reoperation, virtual planning and surgical protocol have been exposed.L’articulation temporomandibulaire (ATM) est probablement l’articulation humaine la plus complexe. Comme pour toutes les articulations, son remplacement prothétique peut être indiqué dans certains cas. D’importantes avancées ont été faites dans la conception des prothèses d’ATM durant les trois dernières décennies et les indications ont été précisées. Le but de notre travail était de faire une mise au point sur les possibilités actuelles de remplacement total de l’ATM. Les indications, les contre-indications, les composants prothétiques, les avantages, les inconvénients, les causes d’échec ou de reprise, la planification virtuelle et le protocole chirurgical ont été précisés

Clinical outcomes and functional recovery after temporomandibular joint replacement: a six-month follow-up study

International audienceTemporomandibular joint replacement (TMJR) is recognized to solve pain and functional limitations when other less invasive strategies failed. TMJR consists in condyle osteotomy (leading to the section of the lateral pterygoid muscle) followed by the fixation of the fossa and the mandibular components. The surgery leads to immediate pain relief and a progressive increase of the mouth opening, assessed by the gap between the upper and lower incisal teeth. Other parameters were rarely considered such as the trajectories of mandibular landmarks (Wojczynska et al. 2019). Our study combines the assessment of the quality of life (QoL) outcomes with quantitative functional measurements – electromyography (EMG) of the masticatory muscles and 3 D mandibular motions – in order to evaluate the mid-term effects of TMJR

Evolution of the activity of the masticatory muscles before and after temporomandibular joint replacement: a clinical and functional study

International audienceTemporomandibular joint replacement (TMJR) is the last resort in the management of end-stage TMJ disorders or diseases. There is a clear consensus about the indications for TMJR and a recent increase of the studies concerning the clinical outcomes (Johnson et al. 2017). The functional recovering, after the surgery, is usually assessed by the maximal incisal opening, but few studies have investigated other functional aspects (Wojczynska et al. 2019). Our goal is to analyse the 3 D kinematic analysis of the mandible combined with electromyography (EMG) of the masticatory muscles to study the functional abilities before and after total TMJR. This paper focuses on the evolution of the muscular activities before and after the surgery, for two patients followed during one year and compared with an asymptomatic group

Three-dimensional study of the facial artery and its cutaneous branches

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