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Reptiles, like all animals presented in our veterinary structures, benefit from constant progress in ophthalmology. After a brief reminder of the ocular specificities of these species, 4 examples of current events in this field are presented in this presentation. First of all, news in anatomo-physiology, displaying of the spectacle vascularization in Ophidians without preparation, in non sedated animals. Then, updating in eye examination with the use of OCT (Optical Coherence Tomography) in Reptiles. Next, news about eye diseases with an original description of a case of ankyloblepharon in a Saurian. Finally, news in surgical treatment with the study of a reconstruction technique after enucleation in an Ophidian., Les Reptiles, comme tous les animaux présentés dans nos structures vétérinaires, bénéficient des progrès constants en ophtalmologie. Après un bref rappel des spécificités oculaires de ces espèces, 4 exemples d’actualités dans ce domaine sont présentés dans cet exposé. Tout d’abord, actualité concernant l’anatomo-physiologie avec la mise en évidence, sans préparation, sur l’animal vigile, de la vascularisation de la lunette des Ophidiens. Puis actualité concernant une méthode d’examen oculaire avec l’utilisation de l’OCT (Optical Coherence Tomography = Tomographie par Cohérence Optique) chez les Reptiles. Ensuite, actualité concernant les affections oculaires avec un exemple de description d’un cas d’ankyloblépharon chez un Saurien. Pour finir, actualité concernant la thérapeutique avec l’étude d’une technique de reconstruction après énucléation chez un Ophidien., Rival Franck. Actualités en ophtalmologie des reptiles. In: Bulletin de l'Académie Vétérinaire de France tome 174, 2021. pp. 215-225.

Summary Purpose The goal of this article is to present an infrequent clinical case and to review the available literatura, with an emphasis on ophthalmological symptoms. Methods We present the case of a 4-year-old girl with a large dentigerous cyst on the maxillary bone, who had long-standing unilateral epiphora associated with progressive ocular dystopia, facial asymmetry and ipsilateral amblyopia. A multidisciplinary approach was taken by the maxillofacial surgery, ophthalmology and optometry teams. This included systemic antibiotic administration, surgical cyst drainage and amblyopia treatment. The literature review was carried out in the MEDLINE database through the free electronic access to PubMed in March 2020. Results At the 6-month follow-up, the patient was asymptomatic. The most common symptoms of dentigerous cysts are epiphora 36.8%, ocular dystopia 31.2%, diplopia 21.1%, proptosis, nasolacrimal duct obstruction and blurred vision at 10.5%. Amblyopia has not been reported. Conclusions Dentigerous cysts are benign odontogenic cysts, which can be found in the jaw and less frequently on the maxillary bone. They are usually asymptomatic, and the occurrence of ophthalmic complications is very infrequent. Multidisciplinary management is essential to avoiding long-term morbidity of maxillary dentigerous cysts and should include an ophthalmologist.

Background: Blood-retinal barrier cells are known to exhibit a massive phenotypic change during experimental autoimmune uveitis (EAU) development. In an attempt to investigate the mechanisms of blood-retinal barrier (BRB) breakdown at a global level, we studied the gene regulation of total retinal cells and retinal endothelial cells during non-infectious uveitis. Methods: Retinal endothelial cells were isolated by flow cytometry either in Tie2-GFP mice (CD31+ CD45- GFP+ cells), or in wild type C57BL/6 mice (CD31+ CD45- endoglin+ cells). EAU was induced in C57BL/6 mice by adoptive transfer of IRBP1-20-specific T cells. Total retinal cells and retinal endothelial cells from naïve and EAU mice were sorted and their gene expression compared by RNA-Seq. Protein expression of selected genes was validated by immunofluorescence on retinal wholemounts and cryosections and by flow cytometry. Results: Retinal endothelial cell sorting in wild type C57BL/6 mice was validated by comparative transcriptome analysis with retinal endothelial cells sorted from Tie2-GFP mice, which express GFP under the control of the endothelial-specific receptor tyrosine kinase promoter Tie2. RNA-Seq analysis of total retinal cells mainly brought to light upregulation of genes involved in antigen presentation and T cell activation during EAU. Specific transcriptome analysis of retinal endothelial cells allowed us to identify 82 genes modulated in retinal endothelial cells during EAU development. Protein expression of 5 of those genes (serpina3n, lcn2, ackr1, lrg1 and lamc3) was validated at the level of inner BRB cells. Conclusion: Those data not only confirm the involvement of known pathogenic molecules but further provide a list of new candidate genes and pathways possibly implicated in inner BRB breakdown during non-infectious posterior uveitis., SCOPUS: ar.j, info:eu-repo/semantics/published

Periodically driven quantum systems are currently explored in view of realizing novel many-body phases of matter. This approach is particularly promising in gases of ultracold atoms, where sophisticated shaking protocols can be realized and interparticle interactions are well controlled. The combination of interactions and time-periodic driving, however, often leads to uncontrollable heating and instabilities, potentially preventing practical applications of Floquet engineering in large many-body quantum systems. In this work, we experimentally identify the existence of parametric instabilities in weakly interacting Bose-Einstein condensates in strongly driven optical lattices through momentum-resolved measurements, in line with theoretical predictions. Parametric instabilities can trigger the destruction of weakly interacting Bose-Einstein condensates through the rapid growth of collective excitations, in particular in systems with weak harmonic confinement transverse to the lattice axis. Understanding the onset of parametric instabilities in driven quantum matter is crucial for determining optimal conditions for the engineering of modulation-induced many-body systems., SCOPUS: ar.j, info:eu-repo/semantics/published

Background: A 56-year-old Caucasian man presented with a 2-weeks history of decreased vision in the right eye. Vitritis, papillitis, cystoid macular oedema and inferior diffuse retinal infiltration were noticed. Extensive blood work-up, anterior chamber paracentesis with polymerase chain reaction (PCR) and Goldmann-Witmer coefficient, tuberculin skin test (PPD-test), fluorodeoxyglucose Positron Emission Tomography CT scan (FDG-PET/CT), lymph node biopsy and pars plana vitrectomy were performed. Results: Aqueous and vitreous samples were negative for an infectious and a lymphoproliferative etiology. Enlarged hilar and mediastinal lymph nodes were detected by FDG-PET/CT and subsequently biopsied, allowing to confirm the diagnosis of sarcoidosis. After a few months of oral corticosteroid therapy, the inflammation resolved completely and was replaced by atrophic retinal scars. Conclusion: Necrotising retinopathy-like lesions mimicking an infectious process or a lymphoproliferative disorder can be an atypical manifestation of ocular sarcoidosis., SCOPUS: ar.j, info:eu-repo/semantics/published

We propose a method by which the quantization of the Hall conductance can be directly measured in the transport of a one-dimensional atomic gas. Our approach builds on two main ingredients: (1) a constriction optical potential, which generates a mesoscopic channel connected to two reservoirs, and (2) a time-periodic modulation of the channel specifically designed to generate motion along an additional synthetic dimension. This fictitious dimension is spanned by the harmonic oscillator modes associated with the tightly confined channel, and hence, the corresponding "lattice sites" are intimately related to the energy of the system. We analyze the quantum-transport properties of this hybrid two-dimensional system, highlighting the appealing features offered by the synthetic dimension. In particular, we demonstrate how the energetic nature of the synthetic dimension combined with the quasienergy spectrum of the periodically driven channel allows for the direct and unambiguous observation of the quantized Hall effect in a two-reservoir geometry. Our work illustrates how topological properties of matter can be accessed in a minimal one-dimensional setup, with direct and practical experimental consequences., SCOPUS: ar.j, info:eu-repo/semantics/published

International audience; Background: Worldwide, degenerative eye diseases (age-related maculopathy (ARM), cataract, glaucoma) are the main causes of visual impairment and blindness, which contribute to disability in the elderly. Mainly three types of nutritional factors are investigated for their potential protection against eye ageing: antioxidants; lutein and zeaxanthin (carotenoids which accumulate specifically in the eye); omega 3 polyunsaturated fatty acids. Few epidemiological studies have been conducted in this field, particularly in Europe. Objective: The Alienor (Antioxydants, Lipides Essentiels, Nutrition et maladies OculaiRes) Study aims at assessing the associations of eye diseases with nutritional factors, determined from plasma measurements and estimation of dietary intakes. Design, setting and participants: Subjects were recruited in Bordeaux (France) from the ongoing population-based 3C study. In 2006-2008, 963 subjects from the 3C Study, aged 73 years or more, had an eye examination and will have follow-up eye examinations every 2 years. Measurements: Vascular, genetic and nutritional factors were assessed at baseline (1999-2001) and follow-up examinations of the 3C Study. Eye diseases were classified according to international classifications. Results: Nutritional status and vascular disease and risk factors were similar between participants and non participants, except for a slight difference in plasma triglycerides and HDL-cholesterol. As expected, the prevalence of eye diseases was high: early and late ARM (28.4 % and 5.6 %, respectively), open-angle glaucoma and treated ocular hypertension (4.8 % and 10.0 %, respectively), cataract extraction (45.2 %), retinopathy (8.4 %), retinal vein occlusion (1.1 %), epiretinal membrane (3.9 %), current use of artificial tears (17.3 %). Conclusions: This study confirms the high prevalence of eye diseases in the elderly. Its main strength is the combination of nutritional, vascular and genetic information, collected over a 7 year period of time before the first eye examination. It may help design future interventional studies, which might be common with other age-related disorders, because of common nutritional factors.

Hemorrhages in the palpebral conjunctiva (HPCs) have been recorded in patients living in an area endemic for loiasis who developed serious reactions after ivermectin treatment. A study was designed to evaluate the frequency of these lesions, and to identify risk factors associated with their appearance. The conjunctivae of 1,682 patients who complained of reactions were systematically examined. HPCs were found in 41 patients. The initial mean Loa loa microfilaremia in the individuals with HPCs was 14,900 microfilariae (mf) per mL, as compared with 14.5 mf/mL in the other patients. Mansonella perstans microfilaremia and male gender were also associated with HPCs. Post-treatment fundus examinations were performed on 37 patients, and a close relationship was found between the occurrence of HPCs and the presence of retinal lesions. The vascular pathological processes leading to the ocular lesions may be similar to those which occur at the cerebral level in patients harboring high L. loa microfilaremia who develop neurologic troubles after ivermectin treatment. Retinal lesions may represent a special feature of the Loa-related encephalopathies useful for differential diagnosis, and the HPCs may be useful as an alarm sign to identify those individuals who might develop serious reactions after ivermectin treatment.

Regulation of water movement is crucial for normal retinal function. Under physiologicalconditions, water is passively transported, following an osmotic gradient, through retinalpigment epithelial (RPE) cells from the subretinal space to the choroid. During macularoedema, occurring in several eye diseases, fluid distribution is profoundly changed and retinalcells potentially exposed to hyperosmotic conditions. We investigated the effect ofhyperosmotic stress on RPE cells using a microarray approach. Upon exposure 4h to 100mMNaCl or 200mM sucrose, 79 were down-regulated and 72 up-regulated. Three gene ontologycategories were significantly modulated: cell proliferation, transcription from RNApolymerase II promoter and response to abiotic stimulus. FACS analysis further demonstratedthat hyperosmotic stimulation for 24h, cell count and cell proliferation were significantlydecreased, as well as the percentage of cells in G0/G1 and S phases, while the percentage ofcells in G2/M phases increased and apoptosis and necrosis remained unaffected. Accordingly,hyperosmotic conditions induced a decrease of cyclin B1 and D1 expression and an activationof the p38 MAP kinase. In conclusion, our results demonstrate that hypertonic conditionsprofoundly affect RPE cell gene transcription regulating cell proliferation by down-regulationcyclin D1 and cyclin B1 protein expression. These findings may contribute to ourunderstanding of macular oedema pathophysiology., SCOPUS: ar.j, info:eu-repo/semantics/published

The general pathological and ocular studies in an aborted fetus with type II glycogenosis revealed the widespread lysosomal storage of glycogen. Obvious lesions are observed in the viscera, in the skeletal and ocular muscles, and in all ocular tissues except the pigment epithelium of the retina. Brain and heart are relatively spared. Conjunctival and skin biopsies have a diagnostic importance, since specific alterations are evident early in the course of the disease., SCOPUS: ar.j, info:eu-repo/semantics/published