The Pediatric and Young Adult Choroidal and Ciliary Body Melanoma Genetic Study, A Survey by the European Ophthalmic Oncology Group

PURPOSE:To explore the genetic background of choroidal and ciliary body melanoma among children and young adults, with special focus on BAP1 germline variants in this age group. METHODS:Patients under the age of 25 and with confirmed choroidal or ciliary body melanoma were included in this retrospective, multicenter observational study. Nuclear BAP1 immunopositivity was used to evaluate the presence of functional BAP1 in the tumor. Next-generation sequencing using Ion Torrent platform was used to determine pathogenic variants of BAP1, EIF1AX, SF3B1, GNAQ and GNA11 and chromosome 3 status in the tumor or in DNA extracted from blood or saliva. Survival was analyzed using Kaplan-Meier estimates. RESULTS:The mean age at diagnosis was 17 years (range 5.0–24.8). A germline BAP1 pathogenic variant was identified in an 18-year-old patient, and a somatic variant, based mainly on immunohistochemistry, in 13 (42%) of 31 available specimens. One tumor had a somatic SF3B1 pathogenic variant. Disomy 3 and the absence of a BAP1 pathogenic variant in the tumor predicted the longest metastasis-free survival. Males showed longer metastasis-free survival than females (P = 0.018). CONCLUSIONS:We did not find a stronger-than-average BAP1 germline predisposition for choroidal and ciliary body melanoma among children and young adults compared to adults. Males had a more favorable survival and disomy 3, and the absence of a BAP1 mutation in the tumor tissue predicted the most favorable metastasis-free survival. A BAP1 germline pathogenic variant was identified in one patient (1%), and a somatic variant based mainly on immunohistochemistry in 13 (42%).</p

The Pediatric and Young Adult Choroidal and Ciliary Body Melanoma Genetic Study, A Survey by the European Ophthalmic Oncology Group

PURPOSE:To explore the genetic background of choroidal and ciliary body melanoma among children and young adults, with special focus on BAP1 germline variants in this age group. METHODS:Patients under the age of 25 and with confirmed choroidal or ciliary body melanoma were included in this retrospective, multicenter observational study. Nuclear BAP1 immunopositivity was used to evaluate the presence of functional BAP1 in the tumor. Next-generation sequencing using Ion Torrent platform was used to determine pathogenic variants of BAP1, EIF1AX, SF3B1, GNAQ and GNA11 and chromosome 3 status in the tumor or in DNA extracted from blood or saliva. Survival was analyzed using Kaplan-Meier estimates. RESULTS:The mean age at diagnosis was 17 years (range 5.0–24.8). A germline BAP1 pathogenic variant was identified in an 18-year-old patient, and a somatic variant, based mainly on immunohistochemistry, in 13 (42%) of 31 available specimens. One tumor had a somatic SF3B1 pathogenic variant. Disomy 3 and the absence of a BAP1 pathogenic variant in the tumor predicted the longest metastasis-free survival. Males showed longer metastasis-free survival than females (P = 0.018). CONCLUSIONS:We did not find a stronger-than-average BAP1 germline predisposition for choroidal and ciliary body melanoma among children and young adults compared to adults. Males had a more favorable survival and disomy 3, and the absence of a BAP1 mutation in the tumor tissue predicted the most favorable metastasis-free survival. A BAP1 germline pathogenic variant was identified in one patient (1%), and a somatic variant based mainly on immunohistochemistry in 13 (42%).</p

Severe hypoplasia of the abdominal aorta and its branches in a patient and his daughter.

We report the history of a patient and his daughter, both affected with hypoplasia of the abdominal aorta and its branches, leading to early and dramatic complications. In the index patient, renal ischaemia as a result of severe hypoplasia of the abdominal aorta and the origin of renal arteries led to progressive renal failure and end-stage renal disease at the age of 32 years. Other vascular abnormalities included hypoplasia of the celiac trunk (CT) and superior mesenteric artery (SMA). After a successful kidney transplantation at the age of 40 years, he eventually deceased following an episode of possibly ischaemic acute pancreatitis at 47 years. The patient's daughter suffered from an haemorrhagic stroke at the age of 7 years, which led to the discovery of severe hypertension caused by bilateral narrowing of renal arteries, as well as hypoplasia of CT, SMA, subclavian and pulmonary arteries. Biopsy of the narrowed renal artery of the daughter showed a particular form of fibrodysplasia characterized by an unusual fibrosis of the inner part of the media, just beneath the internal elastic lamina. To our knowledge, this is the first report of familial hypoplasia of the abdominal aorta. It might be the cardinal manifestation of a familial form of fibromuscular dysplasia (FMD). Interestingly, the histological lesions described in the daughter's renal artery differ from the classical form of medial FMD

Substitute or complement? Defining the relative place of EEG and fMRI in the detection of voluntary brain reactions

International audienc

Optical phase contrast imaging of human retinal cells by changing the tissue refractive index

Purpose : Based on oblique partially coherent illumination of transparent samples, we developed a simple custom Optical Phase Imaging (OPI) microscope providing a label-free, semi-quantitative phase contrast imaging. The aim of this study was to explore this ex-vivo modality for retinal imaging and correlate it with standard clinical images and fluorescence microscopy. Methods : Multimodal macular imaging was performed on the flat-mounted retina of an eye presenting an epiretinal membrane with cystoid macular edema, enucleated for a peripheral melanoma. After glial fibrillary acidic protein (GFAP) - aquaporin (AQP)-4 – collagen (Col)-IV co-immuno-labeling and nuclei staining, the retina was cleared by index matching in a medium of refractive index (RI) 1.46 to decrease scattering for high-resolution deep-tissue ex vivo imaging. We performed a comparison of the clinical examinations obtained by Optical Coherence Tomography-Angiography and fluorescein angiography before enucleation, with the images obtained with confocal microscopy and OPI microscopy. Ex-vivo imaging of the retina mounted in a medium with a lower RI (1.40), close to the mean RI of Muller glial cell (MGC), was then repeated to better view the latter cells. Results : The retinal vessels were used as landmarks for correlating all imaging modalities. OPI microscopy allowed for different contrast imaging depending on the RI of the mounting medium. With the high RI medium (1.46), deep contrast imaging of nuclei and intraretinal cysts was obtained. The solution with a RI of 1.4 provided an improvement in the contrast of the retinal structures, from the inner layer (AQP4-positive MGC, epi-retinal membrane, nerve fibers surrounded by GFAP-positive astrocytes) to the photoreceptor segments. No AQP4 labeling was observed inside the cyst. AQP4-positive, GFAP-negative cells were visualized on the ColIV-labeled epi-retinal membrane, demonstrating that the membrane is made of retinal Muller glial cells. Conclusions : This morphological correlative imaging study demonstrated OPI on numerous cellular structures of a human retina by tuning the tissue RI. This label-free in-depth imaging modality offers a new research tool to study the cellular origin of retinal diseases

Effect of the ligand functionalization on the acid-base properties of flexible MOFs

International audienceThe nature of the sites contributing to the acid-base properties of the functionalized highly flexible MIL-53(Fe)-X MOFs, X = CH3, Cl, Br was assessed by Infrared measurements using propyne as a probe molecule since it could act as a proton acceptor via its Ctriple bond; length of mdashC triple bond and as a proton donor through the triple bond; length of mdashCsingle bondH group. These experiments performed in a wide range of propyne concentration were coupled with Density Functional Theory (DFT) calculations performed for all the propyne/MIL-53(Fe) systems based on structures simulated from the in situ X-ray Powder diffraction data. This joint experimental-modeling approach evidenced that the bridging hydroxyl groups present in the MOF structure free of any intra-framework interactions play a preponderant role in the interaction with propyne as hydrogen donor but also as basic sites through the O atom for all functionalized MIL-53(Fe) solids. For X = Cl and Br, an additional interaction is evidenced at higher propyne concentration, involving the halogen atom, which plays the role of basic site toward propyne. These findings are further discussed in light of complementary experimental data issued from gravimetry and microcalorimetry measurements

An Evaluation of UiO-66 for Gas-Based Applications,

International audienceAn Evaluation of UiO-66 for Gas-Based Applications

Effect of the organic functionalization of flexible MOFs on the adsorption of CO2

International audienceThe adsorption of CO2 by a series of functionalized flexible MIL-53(Fe) solids has been evaluated through a combination of in situ X-ray power diffraction, adsorption calorimetry, IR spectroscopy and computer modelling. It appears that (i) strongly polar groups maintain the nonporous structure in its closed form due to strong intra-framework interactions and (ii) less polar functional groups allow only a modulation of the CO2 -framework interactions, in some cases with a disappearance of the initial intra-framework µ2 -OH/X hydrogen bonds, but do not interact directly with the CO2 molecules