Clinical and Genetic Diagnosis of Multiple Osteochondromas in Rwandan Patients

Multiple Osteochondromas (MO) or hereditary multiple exostoses (HME) is an autosomal dominant skeletal disorder mainly characterized by multiple osteochondromas predominantly located at the growth plates of long bones. MO is a genetically heterogeneous disorder and results from mutations in EXT1 and EXT2 genes located on chromosome 8q23-q24 and 11p11-p12. We hereby report a case of a 23-year-old girl who presented characteristic clinical and radiological features of MO. The same clinical signs were observed in her relatives. The p.Arg340Cys mutation in the EXT1 gene was found in the proband confirming the clinical diagnosis. A surgical management was carried out in all affected bones which consisted of excision of the bigger and pain full osteochondromas. The patient was informed of her problem and genetic counseling was offered to the family's members

[Torsion of an ectopic spleen presented as an acute abdomen]. / Torsion d'une rate ectopique se présentant comme un abdomen aigu.

Ectopic spleen is rare and its acute torsion may be fatal while its correct and early diagnosis continues to represent a challenge especially in children. We are reporting a case of a 9 year-old female patient with a one month history of colicky intermittent abdominal pain and whose physical examination revealed a diffuse abdominal tenderness with a large peri-umbilical abdominal mass. A preoperative diagnosis of acute torsion of ectopic spleen was suspected and was confirmed at laparotomy as the spleen pedicle was found twisted. The spleen was congested and gangrenous indicating a splenectomy.

Correlation of Hsp110 expression with caspase-3 and -9 during apoptosis induced by in vivo embryonic exposition to retinoic acid or irradiation in early mouse craniofacial development.

OBJECTIVE: To analyze the expression and role of three proteins (HSP110, caspase-3 and caspase-9) during craniofacial development. DESIGN: Seven pregnant C57Bl/6J mice received, by force-feeding at gestation day 9 (E9), 80 mg/kg of all-trans retinoic acid mixed to sesame oil. Seven pregnant NMRI mice received two grays irradiation at the same gestation day. Control mice of both strains (seven mice for each strain) were not submitted to any treatment. Embryos were obtained at various stages after exposition (3, 6, 12 and 24 h), fixed, dehydrated and embedded. Coronal sections (5 microm) were made. Slide staining occurred alternatively using anti-Hsp110, anti-caspase-3 and anti-caspase-9 immunohistochemistry. RESULTS: Expression of HSP110, caspase-3 and caspase-9 was found in cells of well-known locations of programmed cell death. After retinoic acid exposure, expressions were increased especially in neural crest cells of mandibular and hyoid arches. Quantification of positive cells shows that caspase-9 and Hsp110 were expressed before caspase-3. After irradiation, the expression of the three proteins quickly increased with a maximum 3 h after irradiation. For all three models of apoptosis (physiological, retinoic-induced and irradiation-induced) HSP110 positive cells were more numerous than caspase-3 positive cells. Caspase-3 positive cells were more numerous than caspase-9 positive cells especially in mesectodermal irradiation-induced apoptotic cells. CONCLUSION: The findings show a potential function of HSP110 in apoptosis during embryo development. Caspase-3-expressing cells are more numerous than cells expressing caspase-9, especially irradiation-induced apoptotic neural crest cells. This suggests that other caspases, still to be identified, may activate caspase-3 in this model.

[Expression of caspase 3 and p53 during physiological apoptosis and apoptosis induced by three teratologic agents during early craniofacial development of the mouse embryo]. / L'expression de la caspase 3 et la protéine p53 au cours de l'apoptose physiologique et induite par 3 agents tératogènes au cours du developpement crânimofacial précoce de l'embryon de souris.

The neural crest-derived mesectoderm gives rise to physiologic apoptosis areas in early vertebrate embryos. Certain teratologic agents increase this phenomenon. The purpose of this work was to detect caspase 3 (which is associated with the apoptosis cascade) and p53 in cell death areas, both during physiological apoptosis and during apoptosis induced by three agents (retinoic acid, methyl-triazene, irradiation). Antibody revelation was performed using the aBC peroxidase kit. Quantifications were also performed on histological sections. We observed caspase 3 uptake on some apoptotic and preapoptotic cells in control embryos, and in the embryos exposed to the three teratogens. Immunoreactivity generally preceded the development of cytological features of apoptosis. However, p53 was expressed only in the embryos exposed to ionizing radiation and methyl-triazene (an alkylating agent), but not significantly in embryos exposed to retinoic acid. The present results throw some light on apoptosis mechanisms in several teratologic conditions.

[Histologic and ultrastructural features of cell death both physiological and induced by two different teratogens in branchial arches of mouse embryo]. / Aspects histologiques et ultrastructuraux de la mort cellulaire programmée et induite par deux agents tératogènes dans les arcs viscéraux de l'embryon de souris.

AIM OF THE STUDY: To observe and compare cell death process both physiological and associated with the administration of two different teratogens (irradiation and retinoic acid) inside cephalic mesectoderm. MATERIAL AND METHODS: Irradiated mice: 2 Gy were administered to E 9 embryos. Retinoic acid: 60 mg/kg were gave to E 8 or E 9 embryos. E 9 - 9.5 and E 10 embryos were removed. E 9 - E 9.5 and E 10 control specimens were collected. We used semi-thin sections and ultra-thin sections observed with transmission electron microscope. RESULTS: The major process is apoptosis, which is increased in experimental embryos compared to control specimens. However, autophagy was observed in retinoic acid-treated embryos, while necrosis can rarely occurs after irradiation. CONCLUSION: If the common process seems to be apoptosis, both teratological models differs owing to their respective secondary features. These differences should be explained by the specific pathogenesis of both teratological agents: ligand-receptor reaction and Hox system disruption in retinoic acid administration, direct aggression against DNA and diffuse cell death process following irradiation. Furthermore, congenital malformations induced by these teratogens are quite different. This can be partially explained by a specific blow of different cellular subpopulations.