105 research outputs found
Les cancers de l’orbite etude retrospective à propos de 31 cas
locorégionale rendant le traitement difficile et mutilant. Dans ce travail, nous rapportons notre expérience dans la prise en charge diagnostique et thérapeutique de ces tumeurs. Matériels et méthodes : Notre étude rétrospective a concerné 31 cas de cancers de l’orbite colligés sur 13 ans (1993- 2005). Tous les patients ont bénéficié d’un examen clinique complet, d’une imagerie du massif facial (TDM et/ou IRM) et d’une biopsie de la tumeur. Le traitement a été basé sur la chirurgie, la radiothérapie et/ou la chimiothérapie. Résultats : La symptomatologie clinique était dominée par les signes ophtalmologiques et les algies faciales. L’imagerie a montré dans tous les cas un processus expansif tissulaire à point de départ orbitaire, avec lyse osseuse orbitaire chez 16 patients (51,6%), une extension au massif facial chez 7 patients (22,6%), endocrâniennes chez 6 patients (19,4%) et des formes bilatérales atteignant les deux orbites dans 3 cas (9,7%) l’anatomopathologie montrait une prédominance des lymphomes malins non hodgkiniens (32,3%) et des carcinomes épidermoïdes (32,3%), suivis des rhabdomyosarcomes embryonnaires (19,4 %). Douze patients ont été traités par chirurgie et radiothérapie postopératoire, dix patients par une association radio-chimiothérapie, et neuf autres par une chimiothérapie néo-adjuvante. La survie globale était de 67,8% à 3 ans, 48,4% à 5 ans et 22,6% à 10 ans. Conclusion : Les cancers de l’orbite sont de mauvais pronostic. Un diagnostic précoce et un traitement radical et adapté au type histologique permet d’améliorer la survie et la qualité de vie chez les patients atteints de ces tumeurs.Mots-clés : Orbite, cancer, lymphome, carcinome épidermoïde, rhabdomyosarcom
Finite element prediction of fatigue damage growth in cancellous bone
Cyclic stresses applied to bones generate fatigue damage that affects the bone stiffness and its elastic modulus. This paper proposes a finite element model for the prediction of fatigue damage accumulation and failure in cancellous bone at continuum scale. The model is based on continuum damage mechanics and incorporates crack closure effects in compression. The propagation of the cracks is completely simulated throughout the damaged area. In this case, the stiffness of the broken element is reduced by 98% to ensure no stress-carrying capacities of completely damaged elements. Once a crack is initiated, the propagation direction is simulated by the propagation of the broken elements of the mesh. The proposed model suggests that damage evolves over a real physical time variable (cycles). In order to reduce the computation time, the integration of the damage growth rate is based on the cycle blocks approach. In this approach, the real number of cycles is reduced (divided) into equivalent blocks of cycles. Damage accumulation is computed over the cycle blocks and then extrapolated over the corresponding real cycles. The results show a clear difference between local tensile and compressive stresses on damage accumulation. Incorporating stiffness reduction also produces a redistribution of the peak stresses in the damaged region, which results in a delay in damage fracture
Gastric signet-ring cell carcinoma with hypersecretion of β-Human chorionic gonadotropin and review of the literature
β-Human chorionic gonadotropin (β-HCG) is an embryonic protein secreted by the syncytiotrophoblast of the placenta. The determination of the plasma β-HCG level is routinely used for the diagnosis and the follow-up of germ cell tumors. Some adenocarcinomas have been described as being rarely associated with β-HCG hypersecretion. We report a case of gastric signet-ring cell carcinoma with β-HCG hypersecretion and propose hypotheses to explain the pathogenesis of such hypersecretion. Key Words: β-Human chorionic gonadotropin, gastric signet-ring cell carcinoma
Unilateral aplasia of both cruciate ligaments
Aplasia of both cruciate ligaments is a rare congenital disorder. A 28-year-old male presented with pain and the feeling of instability of his right knee after trauma. The provided MRI and previous arthroscopy reports did not indicate any abnormalities except cruciate ligament tears. He was referred to us for reconstruction of both cruciate ligaments. The patient again underwent arthroscopy which revealed a hypoplasia of the medial trochlea and an extremely narrow intercondylar notch. The tibia revealed a missing anterior cruciate ligament (ACL) footprint and a single bump with a complete coverage with articular cartilage. There was no room for an ACL graft. A posterior cruciate ligament could not be identified. The procedure was ended since a ligament reconstruction did not appear reasonable. A significant notch plasty if not a partial resection of the condyles would have been necessary to implant a ligament graft. It is most likely that this would not lead to good knee stability. If the surgeon would have retrieved the contralateral hamstrings at the beginning of the planned ligament reconstruction a significant damage would have occurred to the patient. Even in seemingly clear diagnostic findings the arthroscopic surgeon should take this rare abdnormality into consideration and be familiar with the respective radiological findings. We refer the abnormal finding of only one tibial spine to as the "dromedar-sign" as opposed to the two (medial and a lateral) tibial spines in a normal knee. This may be used as a hint for aplasia of the cruciate ligaments
CT694 and pgp3 as Serological Tools for Monitoring Trachoma Programs.
Defining endpoints for trachoma programs can be a challenge as clinical signs of infection may persist in the absence of detectable bacteria. Antibody-based tests may provide an alternative testing strategy for surveillance during terminal phases of the program. Antibody-based assays, in particular ELISAs, have been shown to be useful to document C. trachomatis genital infections, but have not been explored extensively for ocular C. trachomatis infections. An antibody-based multiplex assay was used to test two C. trachomatis antigens, pgp3 and CT694, for detection of trachoma antibodies in bloodspots from Tanzanian children (n = 160) collected after multiple rounds of mass azithromycin treatment. Using samples from C. trachomatis-positive (by PCR) children from Tanzania (n = 11) and control sera from a non-endemic group of U.S. children (n = 122), IgG responses to both pgp3 and CT694 were determined to be 91% sensitive and 98% specific. Antibody responses of Tanzanian children were analyzed with regard to clinical trachoma, PCR positivity, and age. In general, children with more intense ocular pathology (TF/TI = 2 or most severe) had a higher median antibody response to pgp3 (p = 0.0041) and CT694 (p = 0.0282) than those with normal exams (TF/TI = 0). However, 44% of children with no ocular pathology tested positive for antibody, suggesting prior infection. The median titer of antibody responses for children less than three years of age was significantly lower than those of older children. (p<0.0001 for both antigens). The antibody-based multiplex assay is a sensitive and specific additional tool for evaluating trachoma transmission. The assay can also be expanded to include antigens representing different diseases, allowing for a robust assay for monitoring across NTD programs
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