Equine glaucoma

Glaucoma is a group of eye diseases characterized by functional damage to the optic nerve and ganglion cells of the retina, usually due to a transient or permanent elevation in intraocular pressure (IOP). The condition occurs infrequently in horses, and is most often a complication of anterior uveitis. Its development is often insidious and can remain asymptomatic until an advanced stage associated with hydrophthalmos and blindness. In horses, an IOP greater than 30 mmHg, measured by applanation or rebound tonometry, in conjunction with compatible clinical features is consistent with a diagnosis of glaucoma. Medical and surgical treatments are directed towards reducing IOP, but glaucoma secondary to equine recurrent uveitis is generally difficult to control. This article summarises the clinical, pathogenesis, diagnostic and therapeutic data of equine glaucomaLe glaucome est une affection oculaire résultant d’une augmentation temporaire ou permanente de la pression intraoculaire (PIO), qui entraîne une atteinte fonctionnelle du nerf optique et des cellules ganglionnaires de la rétine. Peu fréquent chez le cheval, il représente le plus souvent une complication d’une uvéite antérieure. Son développement est souvent insidieux et peut rester ignoré jusqu’à un stade avancé caractérisé par l’hydrophtalmie et la cécité. Une PIO supérieure à 30 mmHg, mesurée par tonométrie à aplanissement ou à rebond, associée à un tableau clinique évocateur est considérée comme une confirmation du diagnostic de glaucome chez le cheval. Les traitements médicaux et chirurgicaux visent à diminuer la PIO, mais le glaucome secondaire à l’uvéite récurrente équine est généralement difficile à contrôler. Cet article présente une synthèse des données cliniques, pathogéniques, diagnostiques et thérapeutiques sur le glaucome équi

Forced assembly by multilayer coextrusion to create oriented graphene reinforced polymer nanocomposites

A potential advantage of platelet-like nanofillers as nanocomposite reinforcements is the possibility of achieving two-dimensional stiffening through planar orientation of the platelets. The ability to achieve improved properties through in-plane orientation of the platelets is a challenge and, here, we present the first results of using forced assembly to orient graphene nanoplatelets in poly(methyl methacrylate)/ polystyrene (PMMA/PS) and PMMA/PMMA multilayer films produced through multilayer coextrusion. The films exhibited a multilayer structure made of alternating layers of polymer and polymer containing graphene as evidenced by electron microscopy. Significant single layer reinforcement of 118% at a concentration of 2 wt % graphene was achieveddhigher than previously reported reinforcement for randomly dispersed graphene. The large reinforcement is attributed to the planar orientation of the graphene in the individual polymer layers. Anisotropy of the stiffening was also observed and attributed to imperfect planar orientation of the graphene lateral to the extrusion flow

Counting RNA pseudoknotted structures

International audienceIn 2004, Condon and coauthors gave a hierarchical classification of exact RNA structure prediction algorithms according to the generality of structure classes that they handle. We complete this classification by adding two recent prediction algo- rithms. More importantly, we precisely quantify the hierarchy by giving closed or asymptotic formulas for the theoretical number of structures of given size n in all the classes but one. This allows to assess the tradeoff between the expressiveness and the computational complexity of RNA structure prediction algorithms

Clinical, electroretinographic and histomorphometric evaluation of the retina in sheep with natural scrapie

Background: The retina is part of the diencephalon in a peripheral location and may be involved in prion diseases. Retinal function and structural changes were assessed in naturally scrapie-affected red face Manech ewes presenting the classical signs of the disease, and clinically healthy age-matched subjects for controls. Ophthalmic examination was done prior to electroretinography (ERG), which was carried out under conditions that allowed photopic and scotopic activities to be assessed. Histomorphometry of the inner and outer retinal layers was performed post-mortem, and retinas were also examined for evidence of abnormal prion protein (PrPSc) accumulation and glial fibrillary acidic protein (GFAP) upregulation as a marker of gliosis. Scrapie status was determined by examination of brain tissue Results: Ocular reflexes and ophthalmoscopy did not reveal any difference between scrapie affected and control animals. Although the light-and dark-adapted ERG responses of both rod-and cone-mediated functions had a similar waveform in scrapie-affected and control sheep, a significant reduction in the amplitude of the ERG a-and b-waves was observed in affected animals compared to controls. These functional alterations were correlated with a substantial loss of cells in the outer nuclear layer (ONL), lengthening and disorganization in photoreceptor segments, and substantial reduction in cellularity and thickness of the inner nuclear layer (INL). The degenerative changes in the INL and ONL were most marked in the central and paracentral areas of the scrapie retinas, and were accompanied in all scrapie retinas by PrPSc deposition in the ganglion cell and synaptic layers. GFAP immunoreactivity was mainly increased in the ganglion cell and inner plexiform layers. Conclusions: No appreciable fundoscopic changes were observed in the scrapie-affected ewes although reproducible changes in retinal function as measured by ERG were observed in these animals. The alterations in the receptoral and post-receptoral pathways corresponded to the degenerative lesions observed in the ONL and INL of the scrapie retinas. The retinal degeneration was associated with prion protein infectivity which presumably spread via the optic nerve

Preparation and characterization of poly(ethylene terephthalate) films coated by chitosan and vermiculite nanoclay

Chitosan (CS) layers are coated on a poly(ethylene terephthalate) (PET) film in order to decrease the oxygen permeability through the polymeric films for food packaging applications. Oxygen transmission rate (OTR) of the 130 μm PET films can be decreased from 11 to only 0.31 cm3/m².day with a coated layer of 2 μm of CS. Additional decrease is obtained with the addition of vermiculite (VMT) to CS matrix in high proportion (40 to 50 w/w%). The OTR of the coated PET films decreased to very low values, below the detection limit of commercial instrumentation (≤0.008 cm3/m2 day). This high-barrier behavior is believed to be due to the brick wall nanostructure, which produces an extremely tortuous path for oxygen molecules

Early T Cell Signalling Is Reversibly Altered in PD-1+ T Lymphocytes Infiltrating Human Tumors

To improve cancer immunotherapy, a better understanding of the weak efficiency of tumor-infiltrating T lymphocytes (TIL) is necessary. We have analyzed the functional state of human TIL immediately after resection of three types of tumors (NSCLC, melanoma and RCC). Several signalling pathways (calcium, phosphorylation of ERK and Akt) and cytokine secretion are affected to different extents in TIL, and show a partial spontaneous recovery within a few hours in culture. The global result is an anergy that is quite distinct from clonal anergy induced in vitro, and closer to adaptive tolerance in mice. PD-1 (programmed death -1) is systematically expressed by TIL and may contribute to their anergy by its mere expression, and not only when it interacts with its ligands PD-L1 or PD-L2, which are not expressed by every tumor. Indeed, the TCR-induced calcium and ERK responses were reduced in peripheral blood T cells transfected with PD-1. Inhibition by sodium stibogluconate of the SHP-1 and SHP-2 phosphatases that associate with several inhibitory receptors including PD-1, relieves part of the anergy apparent in TIL or in PD-1-transfected T cells. This work highlights some of the molecular modifications contributing to functional defects of human TIL

Submicroscopic Deletions at 13q32.1 Cause Congenital Microcoria.

International audienceCongenital microcoria (MCOR) is a rare autosomal-dominant disorder characterized by inability of the iris to dilate owing to absence of dilator pupillae muscle. So far, a dozen MCOR-affected families have been reported worldwide. By using whole-genome oligonucleotide array CGH, we have identified deletions at 13q32.1 segregating with MCOR in six families originating from France, Japan, and Mexico. Breakpoint sequence analyses showed nonrecurrent deletions in 5/6 families. The deletions varied from 35 kbp to 80 kbp in size, but invariably encompassed or interrupted only two genes: TGDS encoding the TDP-glucose 4,6-dehydratase and GPR180 encoding the G protein-coupled receptor 180, also known as intimal thickness-related receptor (ITR). Unlike TGDS which has no known function in muscle cells, GPR180 is involved in the regulation of smooth muscle cell growth. The identification of a null GPR180 mutation segregating over two generations with iridocorneal angle dysgenesis, which can be regarded as a MCOR endophenotype, is consistent with the view that deletions of this gene, with or without the loss of elements regulating the expression of neighboring genes, are the cause of MCOR

Le test de Schirmer chez le cheval

TOULOUSE3-BU Santé-Centrale (315552105) / SudocTOULOUSE-EN Vétérinaire (315552301) / SudocSudocFranceF

Intérêt de l'acide epsilon-aminocaproïque dans le traitement des ulcères épithéliaux chroniques de la cornée chez le chien

L'activité protéolytique liée à la plasmine a été décrite dans le film lacrymal pré-cornéen des chiens atteints d'ulcères cornéens épithéliaux chroniques et contribuerait à retarder la cicatrisation épithéliale. L'efficacité clinique de l'acide epsilon-aminocaproïque (AEAC), déjà décrite dans le traitement de cette affection chez des modèles lagomorphes, a été explorée dans l'espèce canine grâce à cette étude rétrospective. Les dossiers médicaux des chiens atteints de déficits épithéliaux entre Octobre 1997 et Mars 2003 ont été analysés. Le diagnostic a reposé sur la présence d'une perte de substance épithéliale évoluant depuis plus de 10 jours sans cause sous-jacente apparente. A la première consultation, le lambeau épithélial marginal non adhérent a été débridé sous anesthésie locale sur tous les yeux au moyen d'un coton-tige stérile. Sur 34 yeux (28 chiens), un traitement adjuvant consistant en l'instillation locale trois fois par jour d'un collyre à base d'AEAC à 35.7 mg/ml (groupe AEAC) a été réalisé. Dix-sept yeux (16 chiens) ayant reçu uniquement un collyre de gentamicine à 3 mg/ml après desépithélialisation ont été inclus pour servir de groupe contrôle. Après le début du traitement, des suivis cliniques ont été réalisés chaque semaine pendant trois semaines. Les deux groupes de traitement avaient approximativement la même distribution raciale et ne présentaient pas de différence statistique significative (P>0.05) pour l'âge, le genre, le côté affecté et la durée d'évolution de l'ulcère. Les résultats ont montré qu'à la fin de la période de suivi (J21), le taux global de guérison était significativement plus élevé (P=0.0001) dans le groupe AEAC (32/34= 94.1%) que dans le groupe contrôle (7/17=41.2%). Aucun effet secondaire n'a été noté pendant la période d'observation. Cette étude suggère que l'utilisation locale d'AEAC semble bénéfique dans le traitement des pertes épithéliales cornéennes idiopathiques chez le chien et confirme indirectement que le système activateur du plasminogène / plasmine, inhibé par l'AEAC, est impliqué dans la pathogénie de cette affection.TOULOUSE3-BU Santé-Centrale (315552105) / SudocTOULOUSE-EN Vétérinaire (315552301) / SudocSudocFranceF