920 resultados para Degeneração macular


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A Leishmania chagasi localisa-se principalmente nas cellulas reticulo-endotheliaaes dos tecidos. No sangue peripherico, o protozoario é visto com maior facilidade nos periodos iniciaes da infecção, quando pode ser observado livre, mais frequentemente no plasma de polynucleares e raramente no interior de macrophagos. Nas phases ulteriores, o parasito é raro no sangue peripherico e, quando encontrado, acha-se localisado no plasma de cellulas mononucleares. No interior dos leucocytos polynucleares apresentam as leishmanias signaes evidentes de degeneração, emquanto que nos macrophagos manteem o aspecto morphologico normal e as formas de multiplicação ocorrem com frequencia. Nos periodos agudos predominam os aspectos histo-pathologicos que traduzem intensa actividade do systema reticulo-endothelial e, nos periodos chronicos, a proliferação do tecido intesticial. O quadro hematologico é o de uma anemia sem signaes periphericos de regeneração. Os orgãos hematopoieticos demonstram signaes de perturbação funccional traduzida pelo exaggero da actividade que, entretanto, não leva á elaboração completa de globulos vermelhos, e á formação de granulocytos em número sufficiente. O quadro evolutivo da doença é o de uma anemia progressiva accompanhada de cachexia.

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1) Os Cyathodiniidae são ciliados caracterisados morfologicamente pela existência de uma escavação de abertura antero-ventral, o pseudo-peristoma. A ciliatura é constituída por cilios uniformes dispostos em linhas transversas ou obliquas que revestem a parte externa do corpo situado ao nível do pseudo-peristoma onde penetram para revestir a superfície interna deste. Os Cyathodiniidae apresentam duplicidade nuclear nítida, que se manifesta morfologica e funcionalmente. 2) Os Cyathodiniidade não possuem boca e sua nutrição se faz por ormose através a membrana celular. 3) Os Cyathodiniidae não possuem boca e sua nutrição se faz por ormose através a membrana celular. 3) Os Cyathodiniidae se multiplicam por divisão binária que é acompanhada da perda dos cílios e fromação endógena de duas novas ciliaturas. O plano de divisão é longitudinal ou obliquo, isto é, se faz de acordo com as idéias de Chatton e Lwoff perpendicularmente á direção das cinelias. 4) A reorganização se faz exclusivamente por endomixia que é acompanhada da perda dos cílios e formação endógena da nova ciliatura. 5) A endomixia se passa em indivíduos que, quer pela sua morfologia, quer pelas dimensões, não diferem das fórmas neutras. 6) No processo de endomixia o micronúcleo por meio de duas mitoses sucessivas forma 4 nucleos, 3 dos quais degeneram, enquanto o restante vae formar por divisão o novo micronúcleo e a placenta que se transforma posteriormente no novo macro-nucleo. 7) O processo é identico, nos dois gêneros em que se sub-divide a família, diferindo apenas no modo por que se dá a degeneração do macronúcleo e dos restos da divisão do micronúcleo. 8) Enquanto no genero Cyathodinium a degeneração se faz por picnose, no gênero Cyathodinioides, o macronucleo degenera por desagregação em granulos e os restos de divisão do micronucleo, pelo processo de degeneração macronucleiforme descrito por Ivanic, terminando tambem por desagregação em granulos. 9) A degeneração macronucleiforme deve ser interpretada como uma evolução abortada e não como prova de ser o macronúcleo uma organela em degeneração, como pensa Ivanic. 10) Os Cyathodiniidae se transmitem por meio de quistos. 11) Os cyathodiniidae devem ser considerados como ciliados dos quais apresentam os princípios caracteres. São ciliados modificados pela vida parasitaria e seu estudo é improprio para esclarecer a filogenia desse grupo. 12) Os Cyathodiniidae devem ser incluídos na ordem Holotrica, sub-ordem Astomatea.

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1) O A. descreve, no presente trabalho duas novas espécies de um novo gênero de flagelados (Metasaccinobaculus), colocado entre os Oxymo-nadidae, 2) Morfológicamente, caracterizam-se pela existência de um rostelo que juntamente com o aspecto geral e as esferas endoplasmáticas os aproxima dos oximonadideos, e pela presença de um axostilo ondulante dotado de movementos enérgicos, únicos responsáveis pela locomoção do protozoário. Os flagelos foram definitivamente perdidos. 3) No seu ciclo evolutivo o protozoário apresenta duas fórmas perfeitamente distintas: uma fórma jovem que nada livremente no fluido intes¬tinal do termita e uma fórma adulta, fixa pelo rostelo na parede do tubo digestivo do hospedeiro. A forma adulta e sacciforme, com um longo rostelo em cuja extremidade anterior existe um disco de fixação. O ectoplasma é espesso sobretudo na extremidade posterior, e o endoplasma cheio de esferas pardas. O componente cinético extranuclear é constituído por um axostilo ondulante muito cromófilo, por vêzes franjados nos bordos e preso a parede do corpo por uma estrutura tubular. Além desta organela, observa-se ainda dois sistema fibrilares. O primeiro é constituído de fibras rostelares e que ligam a porção ondulante do axostilo à extremidade do rostelo. O outro que denominamos fibrilas cromófobas independentes, nascem na extremidade do rostelo, percorrendo-o lateralmente em tôda a sua extensão e atingindo o corpo, onde se resolvem em feixes secundários que se espalham em todas as direções. O núcleo é formado de traves grosseiras de cromatina, formando um re¬tículo muito irregular. A forma jovem é muito menor, com rostelo e fibrilas cromófobas rudimentares. O axostilo ondulante relativamente muito desenvolvido, se fixa na extremidade posterior. Com o crescimento, este ponto vai-se deslocando em direção à região anterior do corpo. Nota-se perto do ponto de inserção, uma bainha de filamentos finíssimos envolvendo a porção tubular posterior do axostilo, bastante semelhante são de Saccinobaculus. O endoplasma é fortemente cromófilo, mas sem esferas. O núcleo a principio formado de granulos muito finos de cromatina e uniformemente dispersos, apresenta uma ou mais estruturas envolvidas por um halo claro, com a aparência de cariosoma. Cêdo porém desaparecem. 4) Antes da mitose, que é muito semelhante a de O. grandis, o núcleo desprende-se e caí na porção posterior do corpo, por degeneração de tôdas as organelas cinéticas extranucleares. A membrana nuclear persiste. Forma-se um fuso central muito desenvolvido. Os cromosomas são em número imenso, muito finos e irregulares. No lugar onde deveriam estar presentes os centríolos, vê-se um espaço claro circular na superfície do qual se inserem as fibrilas do fuso. Os novos axostilos ondulantes e demais organelas se formam nos pólos da figura mitótica, a partir dos centríolos perceptíveis pela sua imagem negativa, ou por uma estrutura hialina que envolve a figura mitótica, como é sugerido pelo exame de certas preparações (v. texto desenvolvido).

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Foi realizado um estudo histológico da região hipotalâmica anterior humana empregando-se a colocação pela hematoxilina crômica e a impregnação pelo carbonato de prata a fim de comparar os resultados obtidos com os dois métodos. Verificou-se que a impregnação argêntica fornecia imagens equivalentes ás obtidas com a hematoxilina crômica. Todavia, não pode ser empregada isoladamente, devendo-se sempre fazer o controle com a hematoxilina crômica. Em uma segunda parte do trabalho discute-se o fenômeno da degeneração das porções terminais e subterminais das fibras nervosas do feixe supra-óptico-hipofisário, coincidindo com a formação dos chamados "corpos de Herring". Conceitua-se estes neurônios que formam os núcleos supra-ópticos e paraventricular como um tipo de célula glandular, não obstante sua natureza neuronal, cuja eliminação do produto de elaboração coincide com a desagregação do pólo apical da célula.

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Um menino de quatro anos de idade, natural e residente em Salvador, Bahia, apresentou uma doença febril, de curso rápido com febre, icterícia, dores abdominais, agitação psicomotora, coma e morte no 7º dia do internamento. Histologicamente o fígado exibiu extensa necrose lítica e de coagulação dos hepatócitos, além de degeneração gordurosa aguda ("células em mórula"), infiltração mononuclear e colestase, um quadro considerado tipico da hepatite de Lábrea. A existência de tal caso levanta o problema da ocorrência de hepatite de Lábrea fora da Região Amazônica ou aquele de falta de especificidade do quadro histopatológico considerado como típico da referida condição.

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PURPOSE: Glucocorticoids are used to treat macular edema, although the mechanisms underlying this effect remain largely unknown. The authors have evaluated in the normal and endotoxin-induced uveitis (EIU) rats, the effects of dexamethasone (dex) and triamcinolone acetonide (TA) on potassium channel Kir4.1 and aquaporin-4 (AQP4), the two main retinal Müller glial (RMG) channels controlling retinal fluid movement. METHODS: Clinical as well as relatively low doses of dex and TA were injected in the vitreous of normal rats to evaluate their influence on Kir4.1 and AQP4 expression 24 hours later. The dose-dependent effects of the two glucocorticoids were investigated using rat neuroretinal organotypic cultures. EIU was induced by footpad lipopolysaccharide injection, without or with 100 nM intraocular dex or TA. Glucocorticoid receptor and channel expression levels were measured by quantitative PCR, Western blot, and immunohistochemistry. RESULTS: The authors found that dex and TA exert distinct and specific channel regulations at 24 hours after intravitreous injection. Dex selectively upregulated Kir4.1 (not AQP4) in healthy and inflamed retinas, whereas TA induced AQP4 (not Kir4.1) downregulation in normal retina and upregulation in EIU. The lower concentration (100 nM) efficiently regulated the channels. Moreover, in EIU, an inflammatory condition, the glucocorticoid receptor was downregulated in the retina, which was prevented by intravitreous injections of the low concentration of dex or TA. CONCLUSIONS: The results show that dex and TA are far from being equivalent to modulate RMG channels. Furthermore, the authors suggest that low doses of glucocorticoids may have antiedematous effects on the retina with reduced toxicity.

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Purpose: To report a novel maculopathy in a patient with SCA1. To describe autofluorescence findings in family with SCA7 and associated cone-rod retinal dysfunction.Methods: 4 affected patients from two families were assessed to investigate a progressive loss of visual acuity (VA). Examinations included fundus photography, autofluorescence (AF) fundus fluorescein angiogragraphy (FFA) and optical coherence tomography. Electroretinogram (full-field) was performed in 2 affected patients. All patients had color vision testing using Ishihara pseudoisochromatic plates. Molecular analysis was performed in family 2.Results: The patient with known diagnosis of SCA1 had a visual acuity of 20/200 bilaterally and dyschromatopsia. He had saccadic pursuit. Fundus examination showed mild retinal pigment epithelium (RPE) changes at the macula. OCT showed bilateral macular serous detachment, which was not obvious at the FFA and explained his VA. AF imaging showed a central hyperfluorescence. The 45 year old proband from family 2 had a visual acuity of 200/20 and dyschromatopsia. ERG testing showed cone type dysfunction of photoreceptors. Her daughter affected at a younger age had the same ERGs findings. Fundus examination showed mild RPE changes in proband, normal findings in her daughter. AF imaging of both patients showed a ring of high density AF around the fovea. The ring was also obvious on near infrared AF. Later onset of gait imbalance led to the diagnosis of SCA7Conclusions: Within the group of spinocerebellar ataxias, only the type 7 is associated with retinal dysfunction. We present the first report of maculopathy associated with SCA1 causing severe vision loss. The ring of high density AF in SCA7 confirmed an early retinal photoreceptor dysfunction in patient with normal fundus.

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PURPOSE: Milk fat globule-epidermal growth factor-factor VIII (MFGE8) is necessary for diurnal outer segment phagocytosis and promotes VEGF-dependent neovascularization. The prevalence of two single nucleotide polymorphisms (SNP) in MFGE8 was studied in two exsudative or "wet" Age-related Macular Degeneration (AMD) groups and two corresponding control groups. We studied the effect of MFGE8 deficiency on retinal homeostasis with age and on choroidal neovascularization (CNV) in mice. METHODS: The distribution of the SNP (rs4945 and rs1878326) of MFGE8 was analyzed in two groups of patients with "wet" AMD and their age-matched controls from Germany and France. MFGE8-expressing cells were identified in Mfge8(+/-) mice expressing ß-galactosidase. Aged Mfge8(+/-) and Mfge8(-/-) mice were studied by funduscopy, histology, electron microscopy, scanning electron microscopy of vascular corrosion casts of the choroid, and after laser-induced CNV. RESULTS: rs1878326 was associated with AMD in the French and German group. The Mfge8 promoter is highly active in photoreceptors but not in retinal pigment epithelium cells. Mfge8(-/-) mice did not differ from controls in terms of fundus appearance, photoreceptor cell layers, choroidal architecture or laser-induced CNV. In contrast, the Bruch's membrane (BM) was slightly but significantly thicker in Mfge8(-/-) mice as compared to controls. CONCLUSIONS: Despite a reproducible minor increase of rs1878326 in AMD patients and a very modest increase in BM in Mfge8(-/-) mice, our data suggests that MFGE8 dysfunction does not play a critical role in the pathogenesis of AMD.

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Purpose: to describe a case of probable bilateral diffuse uveal melanocytic proliferation (BDUMP) with scleral involvement, free from systemic malignancies and cataract. Methods: fifty months of follow up with recurrent complete ophthalmological examinations, including fundus photography, fluorescein/indocyanine green angiography (FA) and optical coherence tomography (OCT). Investigations also included an electroretinography (ERG) and histological examination of scleral biopsy. Extraocular malignancies were repeatedly searched. Results: the patient was a 61 year-old Italian man with chronic hepatitis type C. At first visit his best corrected visual acuity (BCVA) was 20/32 in OS and 20/25 in OD. Funduscopy showed multiple patch-shaped pigmented alterations involving macular region and mid retinal periphery. FA showed corresponding areas of late-phase hyperfluorescent pinpoints (figure 1a, OS) and intemediate-phase hypocyanescence (figure 1b, OS), with subtle serous neurosensory retinal detachment confirmed by OCT. Photopic and scotopic ERG tested normal. Systemic prednisone was administered for one month without any improvement. After ten months round pigmentary lesions appeared also in superior scleral surface of both eyes. Biopsy allowed to disclose slightly pigmented spindle cells. BCVA worsened for further 10 months, with enlargement of FA alteration areas but lenses still clear. After 30 months spontaneous coalescence and atrophy of retinal lesions started, paralleled by progressive visual recovery. At the end of our follow up BCVA was 20/25 in OU while scleral pigmentary lesions remained unchanged. Conclusions: we report the case of a patient with main features of BDUMP and some unusual findings. Although not all classical diagnostic criteria were fulfilled, the presence of scleral pigmented lesions and spontaneous visual recovery may enlarge clinical spectrum of the disease.

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PURPOSE: To assess the role of vitreoretinal surgery in maximizing treatment outcome following complications after proton therapy for uveal melanoma and to evaluate its safety. METHODS: Retrospective chart study on 21 patients (2% of a total of 1,005 treated by proton therapy between January 2003 and August 2007) who had developed a complication requiring vitreoretinal surgery. Mean/median total follow-up after irradiation was 43/43 months (range, 12-70 months). RESULTS: Indications for surgery included vitreous hemorrhage (n = 13), epimacular membrane (n = 5), rhegmatogenous retinal detachment (n = 1), combined vitreous hemorrhage with total serous retinal detachment (n = 1), and vitritis (n = 1). Mean/median interval for vitreoretinal surgery after irradiation was 21/20 months (range, 4-45 months), and mean/median follow-up after pars plana vitrectomy was 22/23 months (range, 2-56 months). Pars plana vitrectomy was combined with retinal photocoagulation (n = 5), air/gas (n = 5), or silicone oil tamponade (n = 1). Mean Snellen visual acuity was 20/200 (0-20/40) before and 20/100 (0-20/25) after pars plana vitrectomy. A transient postoperative rise in intraocular pressure was measured in seven patients. Four patients developed phthisis bulbi. CONCLUSION: Vitreoretinal surgery was efficient in maximizing treatment outcome after proton therapy, as it allowed a better oncologic follow-up. Pars plana vitrectomy permitted panretinal photocoagulation to avoid neovascular glaucoma or retinal detachment repair. Macular surgery improved visual acuity, especially in anterior melanoma, whereas repeated surgery may increase the risk of enucleation.

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La rétinopathie diabétique touche un nombre croissant de personnes, soit quatre millions en Europe, ce chiffre va probablement doubler d'ici 2030. Si l'on considère que 25-30% de ces patients sont atteints de rétinopathie diabétique, un dépistage et un traitement précoce permettent d'éviter les complications oculaires sévères telles que l'oedème maculaire cystoïde où la rétinopathie diabétique proliférative. Un résumé des dernières données de la littérature ophtalmologique est présenté en insistant sur le rôle de l'anti-VEGF (vascular endothelial growth factor) et des implants intravitréens de corticostéroïdes pour une pathologie oculaire récemment classée dans les pathologies inflammatoires. Diabetic retinopathy affects an increasing number of persons, about 4 millions in Europe, a number that will probably double until 2030. If we consider that 25-30% of patients are affected by diabetic retinopathy, an ophthalmologic screening and early therapy will allow a better visual prognosis and avoid severe ocular complications such as diabetic macular edema and proliferative diabetic retinopathy. A summary of current ophthalmologic literature was performed and was focused on the role of anti-VEGF (vascular endothelial growth factor) therapies and intraocular drug delivery of corticosteroids in a pathology that was recently classified in inflammatory pathologies.

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OBJECTIVE: To genetically and phenotypically describe a new ADAM9 homozygous mutation in a consanguineous family from Egypt with autosomal recessive cone-rod dystrophy (arCRD), anterior polar and posterior subcapsular cataract. DESIGN, SETTING AND PARTICIPANTS: The parents and their six children were included. They underwent a complete ophthalmic examination with fundus photography and optical coherence tomography (OCT). INTERVENTION: DNA was extracted from peripheral blood from all family members. Screening for mutations in genes known to be implicated in retinal disorders was done with the IROme, an in-solution enrichment array, followed by high-throughput sequencing. Validation of the results was done by bidirectional Sanger sequencing of ADAM9 exon 14, including exon-intron junctions. Screening of normal controls was done by denaturing high-performance liquid chromatography. RESULTS: arCRD was diagnosed in the mother and two of her children. Bilateral anterior polar and posterior subcapsular cataract was observed in the mother and bilateral dot cataract was diagnosed in three of the four children not affected with arCRD, one of whom also had glaucoma. The characteristics of the arCRD were childhood-onset visual impairment, reorganisation of the retinal pigment epithelium with mid-periphery greyish-white discolouration, attenuated retinal vasculatur and optic disc pallor. A coloboma-like macular lesion was observed in one of the arCRD-affected children. IROme analysis identified a c.1396-2A>G homozygous mutation in the splice acceptor site of intron 13 of ADAM9. This mutation was homozygous in the two children affected by arCRD and in their affected mother. This mutation was heterozygous in the unaffected father and the four unaffected children. CONCLUSIONS AND RELEVANCE: We identified a novel autosomal recessive ADAM9 mutation causing arCRD in a consanguineous Egyptian family. The percentage of arCRD cases caused by mutation in ADAM9 remains to be determined. Few families are reported in the literature to date; hence extensive clinical descriptions of families with ADAM9 mutations are of significant importance.

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Purpose: To phenotype a large 3 generation Swiss family with pattern dystrophy and to report a successful result of treatment with ranibizumab of a subfoveal choroidal neovascularisation (CNV) associated with pattern dystrophy in 1 patient Patients and methods: 4 affected and 3 unaffected patients (3 female 4 male, age range: 19 - 80 years) were assessed with a complete ophthalmologic examination. AF images were taken using Heidelberg Retina Angiograph and the digital color photos, fluorescein angiogragraphy (FFA) using the same TOPCON 501 camera. Electroretinogram (full-field and multifocal) was performed in 1 affected patient. One 48 years old patient developed a subfoveal CNV, which was treated with 2 injections of ranibizumab, at 3 months interval. Blood sample was taken for molecular analysis (screening of the gene RDS). Results: Two patients had a typical fundoscopic appearance of pattern dystrophy with butterfly shaped deposit at the fovea and some peripheral flecks, as shown with AF imaging.. Two others affected patients had a more unusual appearance with some macular atrophy in one or both eyes, surrounded by flecks. The visual acuity ranged from 1.0 to 0.1 according to Snellen EDTRS chart. The patient with subfoveal CNV presented a drop of vision form 1.0 to 0.6 within 10 days prior to the diagnosis and also reported some metamorphopsia. FFA and optical computerized tomography (OCT) confirmed a classic CNV. After the 1st injection her vision improved to 1.0 but persistent metamorphopsia and fluid on OCT motivated a second injection. One month after the second injection the OCT was flat and the patient had no symptoms. The results of RDS screening will be presented at the meeting. Conclusion: We present a family with pattern dystrophy, with some members having an unusual fundus appearance, which was mistaken for an early onset dry AMD. The AF imaging is a useful tool in diagnosing this condition. A CNV associated with pattern dystrophy a rare. This is the first report of a successful treatment of the CNV with anti-VEGF intravitreal injections.