[Radioanatomy of rhinopharyngeal carcinoma]. / Radioanatomie des cancers du rhinopharynx.

Rhinopharyngeal cancer is one of the best indications for conformal radiotherapy with modulated intensity. Due to the high dose gradient, accurate delineation of target volumes and organs at risk is a critical success factor with this technology. This requires a good knowledge of rhinopharyngeal radioanatomy and optimal imaging techniques.

[How to treat brain metastasis in 2012?]. / Métastases cérébrales : quelle prise en charge en 2012 ?

During the last French radiation oncology society annual congress, the therapeutic options for the management of brain metastases were presented. The indications and limits of surgery, stereotactic radiotherapy and whole brain radiotherapy, as well as their benefit in terms of overall survival, local control and improvement of the functional and neurocognitive status were discussed. The prognosis significance of the different phenotypes of breast cancer on the risk for BM as well as their roles in the treatment of brain metastases were also described. Surgery improves overall survival for patients with a single brain metastase and should be considered in the case of symptomatic lesions. The overall survival of patients treated with stereotactic radiotherapy do not differ from that of patients treated with surgery. These treatments should be mainly considered for patients with good performance status, one to three small brain metastases (<3cm) and limited extracranial disease. Whole brain radiotherapy is more and more discussed in adjuvant setting due to potential late neurocognitive toxicity. This toxicity could be improved with the development of techniques sparing the hippocampus. HER2+ and triple-negative breast cancer patients are at increased risk for brain metastases. Prognosis of these patients differs as the overall survival of HER2+ patients has improved with anti-HER2 therapies. The optimal combination of local and systemic therapies remain to be determined.

Combining ability of tropical maize lines for seed quality and agronomic traits.

Studies of genetic effects of early selection of maize based on seed quality traits are rare, especially those that use materials from different heterotic groups. These studies are also useful in tropical environments and for the advancement of sustainable agriculture with cropping during seasons not commonly used for cultivation. We estimated, through diallel crosses, the predominant genetic effects on the expression of agronomic traits and seed quality and on the general combining ability of nine maize lines from commercial hybrids and the specific combining ability of hybrid combinations among them. In the evaluation of seed quality, seven tests were used: first count and final count of seed germination, seedling vigor classification, cold tolerance, seedling emergence rate in a sand seedbed, speed of emergence in a sand seedbed, and speed of emergence index. Plant height, first ear height and grain yield were the estimated agronomic traits. In the diallel analysis, method 3 (model I) proposed by Griffing was used. There was a greater significance of non-additive genetic effects in the genetic control of seed quality of the various lines. The Flash, Dekalb 350 and P 30F80 lines combined high seed quality and high grain yield. For growth during the normal planting season, the combinations CD 3121-1 x P 30F80, Speed x CD 3121-2, Dow 8330 x AG 8080 and Dekalb 350 x CD 3121-2 were the most promising for both seed quality and agronomic traits.

Phenotypical and functional characteristics of in vitro expanded bone marrow mesenchymal stem cells from patients with systemic sclerosis.

BACKGROUND: Mesenchymal stem cells (MSCs) have a potential immunomodulatory role in autoimmune disease; however, the qualitative properties and haematopoietic support capacity of MSCs derived from patients with autoimmune disease is unclear. OBJECTIVES: To further characterise phenotypically and functionally bone marrow (BM)-derived MSCs from patients with systemic sclerosis (SSc). METHODS: Key parameters of BM-derived MSC function and phenotype were assessed in 12 patients with SSc and compared with 13 healthy normal controls. The parameters included the ability to: form colony-forming unit fibroblasts (CFU-F), differentiate along the adipogenic and osteogenic lineages, express cell surface antigens defining the MSCs population, support normal haematopoiesis and suppress in vitro lymphocyte proliferation induced by either anti-CD3epsilon plus anti-CD28 monoclonal antibodies or the mixed lymphocyte reaction. RESULTS: SSc MSCs were shown to have a similar characteristic phenotype, capacities to form CFU-F and to differentiate along adipogenic and osteogenic lineages as those of healthy donor MSCs. The ability of SSc MSCs to support long-term haematopoiesis was also identical to that of controls. Both healthy donor and SSc BM MSCs reduced the proliferation of autologous and allogeneic peripheral blood mononuclear cells in a cell number dependent fashion. CONCLUSIONS: These results show that BM-derived MSCs from patients with SSc under the described culture conditions exhibit the same phenotypic, proliferative, differentiation potential and immunosuppressive properties as their healthy counterparts and could therefore be considered in an autologous setting. Further studies are needed to ensure the quality and safety of large-scale expansion of patient MSCs prior to their potential use in clinical trials.

Bone marrow mesenchymal stromal cells (BM-MSCs) from healthy donors and auto-immune disease patients reduce the proliferation of autologous- and allogeneic-stimulated lymphocytes in vitro.

OBJECTIVES: To investigate the ability of bone marrow (BM)-derived mesenchymal stromal cells (BM-MSCs) in suppressing the proliferation of stimulated lymphocytes across a range of conditions including autologous BM-MSCs derived from autoimmune disease (AD) patients. METHODS: In vitro cultures of BM-MSCs from healthy donors and AD patients were established and characterized by their differentiation potential into adipocytes and osteoblasts, and their fibroblast-colony-forming unit (CFU-F) ability and phenotype by flow cytometry. BM-MSCs (irradiated and non-irradiated) from healthy and AD patients were tested for their ability to suppress the in vitro proliferation of autologous and allogeneic peripheral blood mononuclear cells (PBMC) (from healthy donors and patients suffering from various ADs) stimulated with anti-CD3epsilon antibody alone or in combination with anti-CD28 antibody. The anti-proliferative effect of the BM-MSCs from healthy donors was tested also on transformed B-cell lines as a model of non-antigen-stimulated lymphocytes. RESULTS: BM-MSCs from healthy donors and AD patients reduced the proliferation of autologous and allogeneic PBMCs by up to 90% in a cell dose-dependent fashion. The immunosuppression was independent of the proliferation of the BM-MSCs and was also effective on already proliferating cells. It was independent also of the clinical activity of AD. An MSC dose-dependent pattern of suppression of proliferation was observed also with transformed B-cell lines, similar to that observed with proliferating PBMC. CONCLUSIONS: The BM-MSCs exhibit extensive anti-proliferative properties against lymphocytes under different conditions. This property might offer a form of immunomodulatory cellular therapy for AD patients if further confirmed in animal models.

Engineering of osteoinductive grafts by isolation and expansion of ovine bone marrow stromal cells directly on 3D ceramic scaffolds.

In this work, we investigated whether osteoinductive constructs can be generated by isolation and expansion of sheep bone marrow stromal cells (BMSC) directly within three-dimensional (3D) ceramic scaffolds, bypassing the typical phase of monolayer (2D) expansion prior to scaffold loading. Nucleated cells from sheep bone marrow aspirate were seeded into 3D ceramic scaffolds either by static loading or under perfusion flow and maintained in culture for up to 14 days. The resulting constructs were exposed to enzymatic treatment to assess the number and lineage of extracted cells, or implanted subcutaneously in nude mice to test their capacity to induce bone formation. As a control, BMSC expanded in monolayer for 14 days were also seeded into the scaffolds and implanted. BMSC could be isolated and expanded directly in the 3D ceramic scaffolds, although they proliferated slower than in 2D. Upon ectopic implantation, the resulting constructs formed a higher amount of bone tissue than constructs loaded with the same number of 2D-expanded cells. Constructs cultivated for 14 days generated significantly more bone tissue than those cultured for 3 days. No differences in bone formation were found between samples seeded by static loading or under perfusion. In conclusion, the culture of bone marrow nucleated cells directly on 3D ceramic scaffolds represents a promising approach to expand BMSC and streamline the engineering of osteoinductive grafts.

Dynamic compression of cartilage constructs engineered from expanded human articular chondrocytes.

Recent works have shown that mechanical loading can alter the metabolic activity of chondrocytes cultured in 3D scaffolds. In this study we determined whether the stage of development of engineered cartilaginous constructs (expanded adult human articular chondrocytes/Polyactive foams) regulates the effect of dynamic compression on glycosaminoglycan (GAG) metabolism. Construct maturation depended on the culture time (3-14 days) and the donor (4 individuals). When dynamic compression was subsequently applied for 3 days, changes in GAG synthesized, accumulated, and released were significantly positively correlated to the GAG content of the constructs prior to loading, and resulted in stimulation of GAG formation only in the most developed tissues. Conversely, none of these changes were correlated with the expression of collagen type II mRNA, indicating that the response of chondrocytes to dynamic compression does not depend directly upon the stage of cell differentiation, but rather on the extracellular matrix surrounding the cells.

Anatomical study of the blood supply of the coxal bone: radiological and clinical application.

The aim of this work was to study the arterial blood supply of the coxal bone in order to optimize radiological embolization and to minimize the risk of postoperative osteonecrosis. Ten fresh cadavers were dissected after intra-arterial injection of colored resin. All the collateral vessels running to this bone were described and counted. On 25 dry bones, the vascular foramina were measured with the aid of a millimetric gauge and a vascular map was created. The posterior part of the ilium appears to be twice as well vascularized as the anterior part. Fractures of the posterior arch of the pelvis are theoretically more hemorrhagic. The presence of the iliolumbar artery in contact with the sacroiliac joint increases the risk with open book or shearing fractures. The artery of the ischium, a collateral of the pudendal artery, supplies the posterior and lateral parts of the acetabulum and the artery of the roof of the acetabulum, its superior and lateral parts. The branches of the anterior and posterior divisions of the obturator artery supply the superior part of the surroundings of the obturator foramen and the antero-inferior and postero-inferior parts of the acetabulum. The Kocher approach may injure the artery of the ischium. Letournel's extended lateral approach and Mears' triradiate approach may injure the artery of the ischium and the artery of the roof of the acetabulum. The risk of osteonecrosis appears to be theoretically increased if one adds an endopelvic approach. The anterior approach to the acetabulum appears to be that which theoretically leads to the least devascularization. The French version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00276-002-0029-2.