Anatomically constrained CT image translation for heterogeneous blood vessel segmentation

Anatomical structures such as blood vessels in contrast-enhanced CT (ceCT) images can be challenging to segment due to the variability in contrast medium diffusion. The combined use of ceCT and contrast-free (CT) CT images can improve the segmentation performances, but at the cost of a double radiation exposure. To limit the radiation dose, generative models could be used to synthesize one modality, instead of acquiring it. The CycleGAN approach has recently attracted particular attention because it alleviates the need for paired data that are difficult to obtain. Despite the great performances demonstrated in the literature, limitations still remain when dealing with 3D volumes generated slice by slice from unpaired datasets with different fields of view. We present an extension of CycleGAN to generate high fidelity images, with good structural consistency, in this context. We leverage anatomical constraints and automatic region of interest selection by adapting the Self-Supervised Body Regressor. These constraints enforce anatomical consistency and allow feeding anatomically-paired input images to the algorithm. Results show qualitative and quantitative improvements, compared to stateof-the-art methods, on the translation task between ceCT and CT images (and vice versa).Comment: Accepted at BMVC 202

Research perspectives in the etiology of congenital anorectal malformations using data of the International Consortium on Anorectal Malformations: evidence for risk factors across different populations

Contains fulltext : 89406.pdf (publisher's version ) (Closed access)PURPOSE: The recently established International Consortium on Anorectal Malformations aims to identify genetic and environmental risk factors in the etiology of syndromic and nonsyndromic anorectal malformations (ARM) by promoting collaboration through data sharing and combined research activities. METHODS: The consortium attempts to recruit at least 1,000 ARM cases. DNA samples are collected from case-parent triads to identify genetic factors involved in ARM. Several genetic techniques will be applied, including SNP arrays, gene and whole exome sequencing, and a genome-wide association study. Questionnaires inquiring about circumstances before and during pregnancy will be used to obtain environmental risk factor data. RESULTS: Currently, 701 ARM cases have been recruited throughout Europe. Clinical data are available from all cases, and DNA samples and questionnaire data mainly from the Dutch and German cases. Preliminary analyses on environmental risk factors in the Dutch and German cohort found associations between ARM and family history of ARM, fever during first trimester of pregnancy and maternal job exposure to cleaning agents and solvents. CONCLUSION: First results show that both genetic and environmental factors may contribute to the multifactorial etiology of ARM. The International Consortium on Anorectal Malformations will provide possibilities to study and detect important genes and environmental risk factors for ARM, ultimately resulting in better genetic counseling, improved therapies, and primary prevention.1 november 201

Immature Cryopreserved Ovary Restores Puberty and Fertility in Mice without Alteration of Epigenetic Marks

BACKGROUND: Progress in oncology could improve survival rate in children, but would probably lead to impaired fertility and puberty. In pre-pubertal girls, the only therapeutic option is the cryopreservation of one ovary. Three births have been reported after reimplantation of cryopreserved mature ovary. Conversely, reimplantation of ovary preserved before puberty (defined as immature ovary) has never been performed in humans. METHODOLOGY/PRINCIPAL FINDINGS: In order to analyze ovarian function, we performed transplantation using fresh or cryopreserved immature grafts in pre-pubertal or adult mice. Puberty as well as cyclic hormonal activity was restored. All follicle populations were present although a significant reduction in follicle density was observed with or without cryopreservation. Although fertility was restored, the graft is of limited life span. Because ex vivo ovary manipulation and cryopreservation procedure, the status of genomic imprinting was investigated. Methylation status of the H19 and Lit1 Imprinting Control Regions in kidney, muscle and tongue of offsprings from grafted mice does not show significant alteration when compared to those of unoperated mice. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that immature ovarian grafting can restore spontaneous puberty and fertility. However, these data suggest that follicle depletion leads to premature ovarian failure. This study addresses the very important epigenetics issue, and provides valuable information to the study of ovarian transplantation suggesting that these procedures do not perturb normal epigenetics marks. These results are highly relevant to the reimplantation question of immature cortex in women

Pathologies obstructives intestinales anténatales et anomalies du plexus nerveux myentérique

Les troubles de la motricité intestinale rencontrés dans les malformations congénitales du tube digestif posent des problèmes de prise en charge néonatale. Un modèle expérimental d atrésie du grêle a été mis au point. Des études phénotypiques et fonctionnelles ont été réalisées en comparant les deux segments de part et d autre de l obstacle. La réponse contractile pendant la stimulation électrique en amont était supérieure à la réponse en aval (0.38+-0.22 N vs. 0.23+-0.08 N; p=0,001). De plus, la réponse contractile au carbachol débutait à des concentrations 100 fois plus faibles en amont qu en aval. Ces modifications motrices étaient associées à une augmentation de la proportion de neurones cholinergiques excitateurs ChAT en amont par rapport à l aval (13,2+/-6,2% vs. 7,5+/-4,3%; p=0,002) sans différence pour les neurones inhibiteurs NOS. Une évaluation phénotypique a été réalisée chez 8 patients pris en charge pour une atrésie du grêle. La proportion des neurones cholinergiques tendait à être supérieure dans les segments d amont par rapport aux segments d aval (38+-16% vs. 25+-12%; p=0,31) et les taux d expressions des ARNm de ChAT étaient augmentés en amont par rapport à l aval (p=0,004), ainsi que VIP (p=0.008) et SP (p=0.008). Ces différences neuronales étaient associées à une augmentation de l expression en amont de GFAP (p=0.008), GDNF (p=0.02) et BDNF (p=0.008). Ces résultats montrent que l occlusion anténatale induit des modifications fonctionnelles et phénotypiques de part et d autre de l obstacle. Des capacités contractiles et un tonus cholinergique différents entre les segments remis en continuité pourraient être à l origine des troubles moteurs observésPARIS-BIUP (751062107) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Resection of Presacral Mass in Currarino Syndrome is Mandatory

IF 2.646International audienc

Malignant transformation of presacral mass in Currarino syndrome

International audienc

A new rat model of prenatal bowel obstruction: development and early assessment.

International audiencePURPOSE: Although intestinal motility disorders often complicate the postoperative surgical management of newborns with congenital intestinal atresia, their pathogenesis remains unclear. Animal models of prenatal intestinal obstruction have been mainly developed in the lamb and the chicken. Despite new insights brought by these models, they have one or more limitations, such as high fetal mortality rates, high costs, long gestation periods, and an insufficient number of fetuses per litter. Moreover, some species are phylogenetically distant from mammals. METHODS: We developed a reproducible model of prenatal intestinal obstruction in the rat to study the histologic changes induced by the obstruction. We report, the technical devices and the first assessment of this atresia model in a didactic way to allow other researchers to easily reproduce the model. RESULTS: Prenatal intestinal obstructions in this study fulfilled all the macroscopic and histologic criteria usually listed by other models of prenatal intestinal obstruction that have been developed in other species. Furthermore with our model, we obtained a high success rate at a low cost. CONCLUSIONS: We presented in this study a reproducible model of prenatal intestinal obstruction in the rat with the macroscopical and histologic features of prenatal intestinal obstruction