970 resultados para Degeneració retinal -- Tractament


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We compared the pupil responses originating from outer versus inner retinal photoreception between patients with isolated hereditary optic neuropathy (HON, n = 8) and healthy controls (n = 8). Three different testing protocols were used. For the first two protocols, a response function of the maximal pupil contraction versus stimulus light intensity was generated and the intensity at which half of the maximal pupil contraction, the half-max intensity, was determined. For the third protocol, the pupil size after light offset, the re-dilation rate and re-dilation amplitude were calculated to assess the post-light stimulus response. Patients with HON had bilateral, symmetric optic atrophy and significant reduction of visual acuity and visual field compared to controls. There were no significant mean differences in the response curve and pupil response parameters that reflect mainly rod, cone or melanopsin activity between patients and controls. In patients, there was a significant correlation between the half-max intensity of the red light sequence and visual field loss. In conclusion, pupil responses derived from outer or inner retinal photoreception in HON patients having mild-to moderate visual dysfunction are not quantitatively different from age-matched controls. However, an association between the degree of visual field loss and the half-max intensity of the cone response suggests that more advanced stages of disease may lead to impaired pupil light reflexes.

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RPE65 is a retinoid isomerase required for the production of 11-cis-retinal, the chromophore of both cone and rod visual pigments. We recently established an R91W knock-in mouse strain as homologous animal model for patients afflicted by this mutation in RPE65. These mice have impaired vision and can only synthesize minute amounts of 11-cis-retinal. Here, we investigated the consequences of this chromophore insufficiency on cone function and pathophysiology. We found that the R91W mutation caused cone opsin mislocalization and progressive geographic cone atrophy. Remnant visual function was mostly mediated by rods. Ablation of rod opsin corrected the localization of cone opsin and improved cone retinal function. Thus, our analyses indicate that under conditions of limited chromophore supply rods and cones compete for 11-cis-retinal that derives from regeneration pathway(s) which are reliant on RPE65. Due to their higher number and the instability of cone opsin, rods are privileged under this condition while cones suffer chromophore deficiency and degenerate. These findings reinforce the notion that in patients any effective gene therapy with RPE65 needs to target the cone-rich macula directly to locally restore the cones' chromophore supply outside the reach of rods.

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Aquest projecte duu a terme una anàlisi de quina és la situació actual quant a la generació de residus de les comarques del Montsià i Baix Ebre, així com de l’estat de les instal·lacions que hi ha quant a tractament de residus. Tenint en compte l’evolució de les quantitats recollides i de la població es fa una prognosi de quina serà la generació de residus en l’horitzó 2008-2012, per així, tenint també en compte la normativa vigent quant a residus, determinar les necessitats i fer una proposta per tal de donar solució a la problemàtica detectada.

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El consum de tabac és causa de pèrdua de salut i la primera causa de mort prematura prevenible en els països desenvolupats. Deixar de fumar aporta grans beneficis per a la salut però hi ha un fet que fa que moltes persones es plantegin no deixar aquest hàbit i és la preocupació pel guany ponderal. Diversos estudis consultats apunten a que es produeix un guany mig de 3-4 kg durant el procés de deshabituació tot i que en un percentatge considerable pot ser superior. Les causes d’aquest guany de pes són degudes a diversos factors: recuperació dels sentits del gust i l’olfacte, l’ansietat, la falta d’activitat física i sobre tot el paper que juga la nicotina. La nicotina augmenta la despesa energètica en l’activitat física, augmenta la termogènesi, incrementa el metabolisme basal, inhibeix la gana, produeix pèrdua de pes, afavoreix el buidament gàstric i recentment s’ha vist en rosegadors que la nicotina regula mecanismes cerebrals a nivell del hipotàlem, això ho fa perquè actua inactivant l’acció de l’enzim adenosine 5′-monophosphate-activated protein kinase (AMPK) provocant una pèrdua de la gana i un augment de la despesa energètica al incrementar la temperatura corporal i accelerar el metabolisme de les grasses. Explicar que la majoria dels efectes tenen una base bioquímica pot ajudar al pacient a comprendre la simptomatologia que pateix en el procés de la deshabituació tabàquica.

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Purpose: To assess the diagnostic accuracy of the Heidelberg Retinal Tomograph 3 (HRT3) as a screening device in comparison with the reference standard of Octopus standard automated perimetry results (SAP) combined with clinical findings. Methods: All patients underwent screening examinations and investigations within a single day. Abnormal screening results were classified as follows: The HRT3: Either "borderline" or "outside normal limits" using the global Moorfields classification (MFC); SAP and clinical exam: A mean defect > 2.4 dB or "outside normal limits" clear text analysis of SAP; and one of the following i) IOP > 21 mmHg, ii) Van Herrick < ¼, iii) cup disc ratio > 0.55, iv) optic nerve head abnormality, v) narrow iridocorneal angle or vi) evidence of peripheral anterior synechiae on gonioscopy. Results: The mean age of the participants was 59.9 years (± 14.8 [21, 91]). Twenty-three subjects (16 %) were classified as abnormal on SAP and clinical exam. The HRT3 classification had a sensitivity of 30 % (95 % CI [16 %, 51 %]) with associated specificity of 58 % (95 % CI [49 %, 66 %]). Of the sixty subjects classified as borderline or outside normal limits with the HRT MFC global result, seven subjects were also abnormal according to SAP and clinical exam. Conclusion: The results suggest that the HRT3 may not be suitable as a sole screening device; however, further investigation is necessary.

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Background: The aim of this study was to evaluate the stability over time of the individually defined interval of intravitreal ranibizumab injection (IVR) for the treatment of recurrent macular edema (ME) in central retinal vein occlusion (CRVO). Patients and Methods: A case series of treatment naïve patients followed in the Jules Gonin Eye Hospital for macular edema due to central retinal vein occlusion is presented. Patients were treated monthly with IVR until complete absence of fluid on qualitative SD-OCT with a minimum of 5 monthly IVR. Thereafter, they were followed according to a modified treat and extend regimen (mTER). Results: Twelve eyes (12 patients) with ME due to CRVO were included. The mean follow-up period was 31.3 months. Analysis showed that best corrected visual acuity (BCVA), central macular thickness and qualitative spectral domain optical coherence tomography (SD-OCT) showed comparable results under monthly interval, after titration of an individualized interval and when performed in a series. 78 % of treating intervals were within ± 2 weeks of the first individually adjusted interval. The mean first defined interval was 4.3 weeks and the mean interval over time was 5.5 weeks (p = 0.003). There was a trend towards longer interval over time. Conclusion: The adjusted interval of retreatment of patients with ME due to CRVO showed a high stability with a trend toward longer duration over time. An mTER regimen seems to be valuable to follow patients with ME with good stabilization of VA.

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El treball que es presenta a continuació és una recerca aplicada, consistent en l’anàlisi descriptiva d’una mostra d’infants i adolescents de 5 a 19 anys atesos al projecte “Cases d’Infants” des del desembre de 2010 fins al juliol de 2013. Aquesta investigació pretén donar a conèixer la nova perspectiva o paradigma d’atenció a la infància i l’adolescència a Catalunya que neix de la Llei dels Drets i les Oportunitats de la Infància i l’Adolescència (LDOIA, maig de 2010): basada en la prevenció, el model sistèmic i de complexitat, la col·laboració de la família com a element de canvi, el treball en xarxa i interprofessionalitat, la participació dels infants i adolescents, i la territorialitat, principalment. Un cop feta aquesta aproximació teòrica, s’ha concretat identificant aquesta nova perspectiva al projecte pilot “Cases d’Infants” (nascut al setembre de 2010), el qual desplega les actuacions que sorgeixen d’aquesta filosofia de treball i suport. Per a elaborar aquesta recerca s’ha emprat un disseny d’investigació no experimental descriptiu, on s’han associat i comparat variables per tal d’identificar interferències en les relacions –a través de proves estadístiques-, i proposar una certa tendència i pronòstic de les característiques del perfil atès al projecte i les interferències d’algunes variables amb el recurs final de l’infant o adolescent. Finalment, s’extreuen unes conclusions en relació a la bibliografia inicial i els resultats obtinguts en l’anàlisi de la mostra estudiada.

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Actualment en les industries farmacèutiques per aconseguir un producte amb unes condicionsespecifiques necessiten una sèrie de matèries primes per aconseguir-ho. L’aigua, es una de lesmes importants, d’aquí a la utilització d’una planta de tractament ja que ha de complir una sèriede requisit de qualitat determinats. Actualment en les industries farmacèutiques per aconseguir un producte amb unes condicionsespecifiques necessiten una sèrie de matèries primes per aconseguir-ho. L’aigua, es una de lesmes importants, d’aquí a la utilització d’una planta de tractament ja que ha de complir una sèriede requisit de qualitat determinats. Físicament, una planta d’aigua es podria descriure com un sistema estructurat de canonades idipòsits per on circula aigua i s’acumula mentre es depurada de forma continua. A mesura ques’aconsegueixen les condicions de puresa desitjades, el líquid es desvia a un altre anellanomenat llaç, en aquest s’acumula en un moviment circulatori constant mentre que les sevescaracterístiques es mantenen vigilades.Des de el llaç. L’aigua pura es distribueix per les diferents zones de la instal•lació, a unatemperatura determinada, a traves de sortidors anomenats punts d’us (POU) ((Point Of Use). El control es farà amb autòmat siemens S7-300 i una pantalla tàctil utilitzant comunicacióprofibus entre ells. Esta previst comunicació amb una scada existent, per intercanviar dadesnomés de visualització de l’estat de la planta. A partir d’un mòdul de teleservei serà possible lacomunicació amb el programa de l’autòmat via mòdem.La combinació de PLC mes pantalla tàctil esdevé una solució robusta i fiable, cosa quegaranteix una gran fiabilitat de la màquina

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A 48-year-old man was examined 24 months after medial and surgical treatment of an isolated well-circumscribed right occipital lobe abscess. An asymptomatic residual left homonymous inferior scotoma was present. Fundus examination revealed temporal pallor of both optic discs, and optical coherence tomography (OCT) revealed mild temporal loss of retinal nerve fiber layer in both eyes. No relative afferent pupillary defect was present. Assessment of the retinal ganglion cell layer demonstrated homonymous thinning in a pattern corresponding to the homonymous visual field loss. There were no abnormalities of the lateral geniculate nuclei or optic tracts on review of the initial brain computed tomography and follow-up magnetic resonance imaging. We believe our patient showed evidence of transsynaptic retrograde degeneration after an isolated right occipital lobe lesion, and the homonymous neuronal loss was detected on OCT by assessing the retinal ganglion cell layer.

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We have identified and characterized a spontaneous Brown Norway from Janvier rat strain (BN-J) presenting a progressive retinal degeneration associated with early retinal telangiectasia, neuronal alterations, and loss of retinal Müller glial cells resembling human macular telangiectasia type 2 (MacTel 2), which is a retinal disease of unknown cause. Genetic analyses showed that the BN-J phenotype results from an autosomal recessive indel novel mutation in the Crb1 gene, causing dislocalization of the protein from the retinal Müller glia (RMG)/photoreceptor cell junction. The transcriptomic analyses of primary RMG cultures allowed identification of the dysregulated pathways in BN-J rats compared with wild-type BN rats. Among those pathways, TGF-β and Kit Receptor Signaling, MAPK Cascade, Growth Factors and Inflammatory Pathways, G-Protein Signaling Pathways, Regulation of Actin Cytoskeleton, and Cardiovascular Signaling were found. Potential molecular targets linking RMG/photoreceptor interaction with the development of retinal telangiectasia are identified. This model can help us to better understand the physiopathologic mechanisms of MacTel 2 and other retinal diseases associated with telangiectasia.

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Inherited retinal dystrophies are phenotypically and genetically heterogeneous. This extensive heterogeneity poses a challenge when performing molecular diagnosis of patients, especially in developing countries. In this study, we applied homozygosity mapping as a tool to reduce the complexity given by genetic heterogeneity and identify disease-causing variants in consanguineous Pakistani pedigrees. DNA samples from eight families with autosomal recessive retinal dystrophies were subjected to genome wide homozygosity mapping (seven by SNP arrays and one by STR markers) and genes comprised within the detected homozygous regions were analyzed by Sanger sequencing. All families displayed consistent autozygous genomic regions. Sequence analysis of candidate genes identified four previously-reported mutations in CNGB3, CNGA3, RHO, and PDE6A, as well as three novel mutations: c.2656C > T (p.L886F) in RPGRIP1, c.991G > C (p.G331R) in CNGA3, and c.413-1G > A (IVS6-1G > A) in CNGB1. This latter mutation impacted pre-mRNA splicing of CNGB1 by creating a -1 frameshift leading to a premature termination codon. In addition to better delineating the genetic landscape of inherited retinal dystrophies in Pakistan, our data confirm that combining homozygosity mapping and candidate gene sequencing is a powerful approach for mutation identification in populations where consanguineous unions are common.

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Mast cells are important in the initiation of ocular inflammation, but the consequences of mast cell degranulation on ocular pathology remain uncharacterized. We induced mast cell degranulation by local subconjunctival injection of compound 48/80. Initial degranulation of mast cells was observed in the choroid 15 minutes after the injection and increased up to 3 hours after injection. Clinical signs of anterior segment inflammation paralleled mast cell degranulation. With the use of optical coherence tomography, dilation of choroidal vessels and serous retinal detachments (SRDs) were observed and confirmed by histology. Subconjunctival injection of disodium cromoglycate significantly reduced the rate of SRDs, demonstrating the involvement of mast cell degranulation in posterior segment disorders. The infiltration of polymorphonuclear and macrophage cells was associated with increased ocular media concentrations of tumor necrosis factor-α, CXCL1, IL-6, IL-5, chemokine ligand 2, and IL-1β. Analysis of the amounts of vascular endothelial growth factor and IL-18 showed an opposite evolution of vascular endothelial growth factor compared with IL-18 concentrations, suggesting that they regulate each other's production. These findings suggest that the local degranulation of ocular mast cells provoked acute ocular inflammation, dilation, increased vascular permeability of choroidal vessels, and SRDs. The involvement of mast cells in retinal diseases should be further investigated. The pharmacologic inhibition of mast cell degranulation may be a potential target for intervention.

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PURPOSE: To define the phenotypic manifestation, confirm the genetic basis, and delineate the pathogenic mechanisms underlying an oculoauricular syndrome (OAS). METHODS: Two individuals from a consanguineous family underwent comprehensive clinical phenotyping and electrodiagnostic testing (EDT). Genome-wide microarray analysis and Sanger sequencing of the candidate gene were used to identify the likely causal variant. Protein modelling, Western blotting, and dual luciferase assays were used to assess the pathogenic effect of the variant in vitro. RESULTS: Complex developmental ocular abnormalities of congenital cataract, anterior segment dysgenesis, iris coloboma, early-onset retinal dystrophy, and abnormal external ear cartilage presented in the affected family members. Genetic analyses identified a homozygous c.650A>C; p.(Gln217Pro) missense mutation within the highly conserved homeodomain of the H6 family homeobox 1 (HMX1) gene. Protein modelling predicts that the variant may have a detrimental effect on protein folding and/or stability. In vitro analyses were able to demonstrate that the mutation has no effect on protein expression but adversely alters function. CONCLUSIONS: Oculoauricular syndrome is an autosomal recessive condition that has a profound effect on the development of the external ear, anterior segment, and retina, leading to significant visual loss at an early age. This study has delineated the phenotype and confirmed HMX1 as the gene causative of OAS, enabling the description of only the second family with the condition. HMX1 is a key player in ocular development, possibly in both the pathway responsible for lens and retina development, and via the gene network integral to optic fissure closure.

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During different forms of neurodegenerative diseases, including the retinal degeneration, several cell cycle proteins are expressed in the dying neurons from Drosophila to human revealing that these proteins are a hallmark of neuronal degeneration. This is true for animal models of Alzheimer's, and Parkinson's diseases, Amyotrophic Lateral Sclerosis and for Retinitis Pigmentosa as well as for acute injuries such as stroke and light damage. Longitudinal investigation and loss-of-function studies attest that cell cycle proteins participate to the process of cell death although with different impacts, depending on the disease. In the retina, inhibition of cell cycle protein action can result to massive protection. Nonetheless, the dissection of the molecular mechanisms of neuronal cell death is necessary to develop adapted therapeutic tools to efficiently protect photoreceptors as well as other neuron types.

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Mitogen-activated protein kinases (MAPKs) are key regulators that have been linked to cell survival and death. Among the main classes of MAPKs, c-jun N-terminal kinase (JNK) has been shown to mediate cell stress responses associated with apoptosis. In Vitro, hypoxia induced a significant increase in 661W cell death that paralleled increased activity of JNK and c-jun. 661W cells cultured in presence of the inhibitor of JNK (D-JNKi) were less sensitive to hypoxia-induced cell death. In vivo, elevation in intraocular pressure (IOP) in the rat promoted cell death that correlated with modulation of JNK activation. In vivo inhibition of JNK activation with D-JNKi resulted in a significant and sustained decrease in apoptosis in the ganglion cell layer, the inner nuclear layer and the photoreceptor layer. These results highlight the protective effect of D-JNKi in ischemia/reperfusion induced cell death of the retina.