200 resultados para Optic Capsule


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BACKGROUND: Giant cell arteritis (GCA) is a systemic segmental vasculitis of unknown etiology, typically affecting elderly patients. Elevated erythrocyte-sedimentation rate (ESR) is usually found in such patients. PATIENTS AND METHODS: One hundred and twenty three patients underwent temporal artery biopsy in our institution between 1977 and 1995. Among them, 66 (53.7%) biopsies were positive (i.e. histologic findings were very suggestive of GCA). The clinical charts from all patients with positive biopsies were retrieved and 47 were eligible for our study (inadequate data in 19 cases). RESULTS: Seven of the 47 patients with positive biopsies (15%) had a normal ESR and 70% (33/47 cases) had neuro-ophthalmic complications including anterior ischemic optic neuropathy, central retinal artery occlusion, choroidal ischemia and extraocular muscle and/or cranial nerve palsy (III, IV, VI). No differences were found between the groups with normal or elevated ESR as 87.5% (6/7 cases) of the group with normal ESR exhibited neuro-ophthalmic complications. CONCLUSIONS: ESR was normal in 15% of our GCA patients and these patients had the same frequency of neuro-ophthalmic complications as the GCA patients with elevated ESR. Thus, our study does not support the previous concept that patients with higher ESR are more at risk for neuro-ophthalmic complications. GCA with normal ESR is not rare and such patients should be investigated with other blood studies (C-reactive protein) and with fluorescein angiography.

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Methods Ten patients with aniridia from 3 families of Egyptian origin underwent full ophthalmologic, general and neurological examination, and blood drawing. Cerebral MRI was performed in the index case of each family. Genomic DNA was prepared from venous leukocytes and direct sequencing of all the exons and intron-exon junctions of the PAX6 gene was performed after PCR amplification. Results Common features observed in the three families included absence of iris tissue, corneal pannus with different degrees of severity and foveal hypoplasia with severely reduced visual acuity. In families 2 and 3, additional findings such as lens dislocation, lens opacities or polar cataract and glaucoma were observed. We identified two novel (c.170-174delTGGGC [p.L57fs17] and c.475delC [p.R159fs47]) and one known (c.718C>T) PAX6 mutations in the affected members of the 3 families. Systemic and neurological examination was normal in all ten affected patients. Cerebral MRI showed absence of the pineal gland in all three index patients. Severe hypoplasia of the brain anterior commissure was associated to the p.L57fs17mutation, absence of the posterior commissure to both p.R159fs47 and p.R240X, and optic chiasma atrophy and almost complete agenesis of the corpus callosum to p.R240X. Conclusions We identified two novel PAX6 mutations in families with severe aniridia from Northern Egypt, an ethnic group which is not well studied. In addition to common phenotype of aniridia and despite normal neurological examination, absence of the pineal gland was observed in all 3 index patients. The heterogeneity of brain anomalies related to PAX6 mutations is underexplored and is highlighted in this study.

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PURPOSE: To use diffusion-tensor (DT) magnetic resonance (MR) imaging in patients with essential tremor who were treated with transcranial MR imaging-guided focused ultrasound lesion inducement to identify the structural connectivity of the ventralis intermedius nucleus of the thalamus and determine how DT imaging changes correlated with tremor changes after lesion inducement. MATERIALS AND METHODS: With institutional review board approval, and with prospective informed consent, 15 patients with medication-refractory essential tremor were enrolled in a HIPAA-compliant pilot study and were treated with transcranial MR imaging-guided focused ultrasound surgery targeting the ventralis intermedius nucleus of the thalamus contralateral to their dominant hand. Fourteen patients were ultimately included. DT MR imaging studies at 3.0 T were performed preoperatively and 24 hours, 1 week, 1 month, and 3 months after the procedure. Fractional anisotropy (FA) maps were calculated from the DT imaging data sets for all time points in all patients. Voxels where FA consistently decreased over time were identified, and FA change in these voxels was correlated with clinical changes in tremor over the same period by using Pearson correlation. RESULTS: Ipsilateral brain structures that showed prespecified negative correlation values of FA over time of -0.5 or less included the pre- and postcentral subcortical white matter in the hand knob area; the region of the corticospinal tract in the centrum semiovale, in the posterior limb of the internal capsule, and in the cerebral peduncle; the thalamus; the region of the red nucleus; the location of the central tegmental tract; and the region of the inferior olive. The contralateral middle cerebellar peduncle and bilateral portions of the superior vermis also showed persistent decrease in FA over time. There was strong correlation between decrease in FA and clinical improvement in hand tremor 3 months after lesion inducement (P < .001). CONCLUSION: DT MR imaging after MR imaging-guided focused ultrasound thalamotomy depicts changes in specific brain structures. The magnitude of the DT imaging changes after thalamic lesion inducement correlates with the degree of clinical improvement in essential tremor.

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betaTC-tet cells are conditionally immortalized pancreatic beta cells which can confer long-term correction of hyperglycemia when transplanted in syngeneic streptozocin diabetic mice. The use of these cells for control of type I diabetes in humans will require their encapsulation and transplantation in non-native sites where relative hypoxia and cytokines may threaten their survival. In this study we genetically engineered betaTC-tet cells with the anti-apoptotic gene Bcl-2 using new lentiviral vectors and showed that it protected this cell line against apoptosis induced by hypoxia, staurosporine and a mixture of cytokines (IL-1beta, IFN-gamma and TNF-alpha). We further demonstrated that Bcl-2 expression permitted growth at higher cell density and with shorter doubling time. Expression of Bcl-2, however, did not inter- fere either with the intrinsic mechanism of growth arrest present in the betaTC-tet cells or with their normal glucose dose-dependent insulin secretory activity. Furthermore, Bcl-2 expressing betaTC-tet cells retained their capacity to secrete insulin under mild hypoxia. Finally, transplantation of these cells under the kidney capsule of streptozocin diabetic C3H mice corrected hyperglycemia for several months. These results demonstrate that the murine betaTC-tet cell line can be genetically modified to improve its resistance against different stress-induced apoptosis while preserving its normal physiological function. These modified cells represent an improved source for cell transplantation therapy of type I diabetes.

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BACKGROUND: The aim of this communication is to describe an unusual and serious complication of retrobulbar anaesthesia for cataract surgery. HISTORY AND SIGNS: A 78-year-old female was referred for visual loss (light perception) 24 hours after apparently uneventful cataract surgery with retrobulbar anaesthesia in her left eye. Fundus examination revealed multiple arterial emboli and a localised retinal detachment. MRI revealed a retrobulbar hypersignal of the optic nerve associated with perineuritis. The cardiovascular examination was normal. We assumed this condition resulted from injection of the anaesthetic mixture into the optic nerve. THERAPY AND OUTCOME: In order to improve retinal circulation and oxygenation, the intraocular pressure was maximally lowered and anticalcic therapy administered, expecting optimal arterial dilatation. Methylprednisolone (1 g/day 3 days i. v., then rapidly tapered) was also added. The retina slowly reattached but visual acuity remained unchanged. CONCLUSIONS: Retrobulbar anaesthesia is routinely used for ocular surgery. Serious complications may still happen, however. This case adds to the previously reported spectrum of complications from retrobulbar anaesthesia.

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A 29-year-old pregnant woman noted acute visual loss following emergent Caesarean section complicated by excessive uterine bleeding. Postoperative visual acuity was count fingers in both eyes. Funduscopic changes were consistent with a diagnosis of anaemia-associated ischaemic optic neuropathy and retinopathy. One month later, because of persistent anaemia and poor visual recovery, blood transfusion was given. Following transfusion, the patient's vision improved over the next 6 months. In an otherwise healthy patient, visual loss associated with postoperative blood loss may still be partially reversible with correction of the anaemia, even after a delayed period of time.

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The complex regional pain syndrome (CRPS) is a rare but debilitating pain disorder that mostly occurs after injuries to the upper limb. A number of studies indicated altered brain function in CRPS, whereas possible influences on brain structure remain poorly investigated. We acquired structural magnetic resonance imaging data from CRPS type I patients and applied voxel-by-voxel statistics to compare white and gray matter brain segments of CRPS patients with matched controls. Patients and controls were statistically compared in two different ways: First, we applied a 2-sample ttest to compare whole brain white and gray matter structure between patients and controls. Second, we aimed to assess structural alterations specifically of the primary somatosensory (S1) and motor cortex (M1) contralateral to the CRPS affected side. To this end, MRI scans of patients with left-sided CRPS (and matched controls) were horizontally flipped before preprocessing and region-of-interest-based group comparison. The unpaired ttest of the "non-flipped" data revealed that CRPS patients presented increased gray matter density in the dorsomedial prefrontal cortex. The same test applied to the "flipped" data showed further increases in gray matter density, not in the S1, but in the M1 contralateral to the CRPS-affected limb which were inversely related to decreased white matter density of the internal capsule within the ipsilateral brain hemisphere. The gray-white matter interaction between motor cortex and internal capsule suggests compensatory mechanisms within the central motor system possibly due to motor dysfunction. Altered gray matter structure in dorsomedial prefrontal cortex may occur in response to emotional processes such as pain-related suffering or elevated analgesic top-down control.

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PURPOSE: To investigate the ability of fibroblast growth factor (FGF) 2-saporin to prevent lens regrowth in the rabbit. METHODS: Chemically conjugated and genetically fused FGF2-saporin (made in Escherichia coli) were used. Extracapsular extraction of the lens was performed on the rabbit, and the cytotoxin either was injected directly into the capsule bag or was administered by FGF2-saporin-coated, heparin surface-modified (HSM) polymethylmethacrylate intraocular lenses. The potential of the conjugate was checked by slit lamp evaluation of capsular opacification and by measuring crystallin synthesis. Toxin diffusion and sites of toxin binding were assessed by immunohistochemistry. Possible toxicity was determined by histologic analysis of ocular tissues. RESULTS: FGF2-saporin effectively inhibited lens regrowth when it was injected directly into the capsular bag. However, high concentration of the toxin induced transient corneal edema and loss of pigment in the iris. Intraocular lenses coated with FGF2-saporin reduced lens regrowth and crystallin synthesis without any detectable clinical side effect. After implantation, FGF2-saporin was shown to have bound to the capsules and, to a lesser extent, to the iris; no histologic damage was found on ocular tissues as a result of implantation of drug-loaded HSM intraocular lenses. CONCLUSIONS: Chemically conjugated (FGF2-SAP) and genetically fused FGF2-saporin (rFGF2-SAP) bound to HSM intraocular lenses can prevent lens regrowth in the rabbit.

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The surrounding capsule of Streptococcus pneumoniae has been identified as a major virulence factor and is targeted by pneumococcal conjugate vaccines (PCV). However, nonencapsulated S. pneumoniae (non-Ec-Sp) have also been isolated globally, mainly in carriage studies. It is unknown if non-Ec-Sp evolve sporadically, if they have high antibiotic nonsusceptiblity rates and a unique, specific gene content. Here, whole-genome sequencing of 131 non-Ec-Sp isolates sourced from 17 different locations around the world was performed. Results revealed a deep-branching classic lineage that is distinct from multiple sporadic lineages. The sporadic lineages clustered with a previously sequenced, global collection of encapsulated S. pneumoniae (Ec-Sp) isolates while the classic lineage is comprised mainly of the frequently identified multilocus sequences types (STs) ST344 (n = 39) and ST448 (n = 40). All ST344 and nine ST448 isolates had high nonsusceptiblity rates to β-lactams and other antimicrobials. Analysis of the accessory genome reveals that the classic non-Ec-Sp contained an increased number of mobile elements, than Ec-Sp and sporadic non-Ec-Sp. Performing adherence assays to human epithelial cells for selected classic and sporadic non-Ec-Sp revealed that the presence of a integrative conjugative element (ICE) results in increased adherence to human epithelial cells (P = 0.005). In contrast, sporadic non-Ec-Sp lacking the ICE had greater growth in vitro possibly resulting in improved fitness. In conclusion, non-Ec-Sp isolates from the classic lineage have evolved separately. They have spread globally, are well adapted to nasopharyngeal carriage and are able to coexist with Ec-Sp. Due to continued use of PCV, non-Ec-Sp may become more prevalent.

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Either 200 or 400 syngeneic islets were transplanted under the kidney capsule of normal or streptozocin-induced diabetic B6/AF1 mice. The diabetic mice with 400 islets became normoglycemic, but those with 200 islets, an insufficient number, were still diabetic after the transplantation (Tx). Two weeks after Tx, GLUT2 expression in the islet grafts was evaluated by immunofluorescence and Western blots, and graft function was examined by perfusion of the graft-bearing kidney. Immunofluorescence for GLUT2 was dramatically reduced in the beta-cells of grafts with 200 islets exposed to hyperglycemia. However, it was plentiful in grafts with 400 islets in a normoglycemic environment. Densitometric analysis of Western blots on graft homogenates demonstrated that GLUT2 protein levels in the islets, when exposed to chronic hyperglycemia for 2 weeks, were decreased to 16% of those of normal recipients. Moreover, these grafts had defective glucose-induced insulin secretion, while the effects of arginine were preserved. We conclude that GLUT2 expression in normal beta-cells is promptly down-regulated during exposure to hyperglycemia and may contribute to the loss of glucose-induced secretion of diabetes.

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Purpose: To date, the genotype/phenotype correlation of p.G56R-linked autosomal dominant retinitis pigmentosa (ADRP) is limited to less than 10 kindred. The purpose of this study is to report an unusual appearance of fundus autofluorescence (AF) with NR2E3 p.G56R-linked ADRP in a single kindred.Methods: Patients were enrolled among three generations in a previously unreported family. Molecular diagnosis was performed on all exons of NR2E3 and a p.G56R mutation was identified in affected family members only. Examinations included fundus photography, visual fields, optical coherence tomography, AF, near-infrared AF and ISCEV-standard electrophysiology (ERG).Results: Among 10 examined family members, 5 were affected. The youngest and oldest patients were 16 and 65 years old, respectively. Fundus examination revealed a range of retinal disorder from normal to optic nerve pallor, attenuated arterial caliber and bone spicule-like pigment deposits. In all patients, AF showed a double hyperfluorescent ring; an inner paramacular ring which extension was comparable among patients and an outer ring along the vascular arcades which extended towards periphery in older patients and became hypofluorescent. Maximal scotopic ERGs when recordable showed an increased a/b wave ratio.Conclusions: A double hyperfluorescent ring on AF is an uncommon observation and might be a specific clinical finding in NR2E3 p.G56R-linked ADRP. The consistency of that finding in all affected members of our 3-generation family confirms a previous study. Further analysis is required to determine whether AF changes are associated with particular retinal layer abnormalities.

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J. Neurochem. (2010) 10.1111/j.1471-4159.2010.06705.x Abstract Retinal excitotoxicity is associated with retinal ischemia, and with glaucomatous and traumatic optic neuropathy. The present study investigates the role of c-Jun N-terminal kinase (JNK) activation in NMDA-mediated retinal excitotoxicity and determines whether neuroprotection can be obtained with the JNK pathway inhibitor, d-form of JNK-inhibitor 1 (d-JNKI-1). Young adult rats received intravitreal injections of 20 nmol NMDA, which caused extensive neuronal death in the inner nuclear and ganglion cell layers. This excitotoxicity was associated with strong activation of calpain, as revealed by fodrin cleavage, and of JNK. The cell-permeable peptide d-JNKI-1 was used to inhibit JNK. Within 40 min of its intravitreal injection, FITC-labeled d-JNKI-1 spread through the retinal ganglion cell layer into the inner nuclear layer and interfered with the NMDA-induced phosphorylation of JNK. Injections of unlabeled d-JNKI-1 gave unprecedentedly strong neuroprotection against cell death in both layers, lasting for at least 10 days. The NMDA-induced calpain-specific fodrin cleavage was likewise strongly inhibited by d-JNKI-1. Moreover the electroretinogram was partially preserved by d-JNKI-1. Thus, the JNK pathway is involved in NMDA-mediated retinal excitotoxicity and JNK inhibition by d-JNKI-1 provides strong neuroprotection as shown morphologically, biochemically and physiologically.

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Purpose: Previous studies of the visual outcome in bilateral non-arteritic anterior ischemic optic neuropathy (NAION) have yielded conflicting results, specifically regarding congruity between fellow eyes. Prior studies have used measures of acuity and computerized perimetry but none has compared Goldmann visual field outcomes between fellow eyes. In order to better define the concordance of visual loss in this condition, we reviewed our cases of bilateral sequential NAION, including measures of visual acuity, pupillary function and both pattern and severity of visual field loss.Methods: We performed a retrospective chart review of 102 patients with a diagnosis of bilateral sequential NAION. Of the 102 patients, 86 were included in the study for analysis of final visual outcome between the affected eyes. Visual function was assessed using visual acuity, Goldmann visual fields, color vision and RAPD. A quantitative total visual field score and score per quadrant was analyzed for each eye using the numerical Goldmann visual field scoring method previously described by Esterman and colleagues. Based upon these scores, we calculated the total deviation and pattern deviation between fellow eyes and between eyes of different patients. Statistical significance was determined using nonparametric tests.Results: A statistically significant correlation was found between fellow eyes for multiple parameters, including logMAR visual acuity (P = 0.0101), global visual field (P = 0.0001), superior visual field (P = 0.0001), and inferior visual field (P = 0.0001). In addition, the mean deviation of both total (P = 0.0000000007) and pattern (P = 0.000000004) deviation analyses was significantly less between fellow eyes ("intra"-eyes) than between eyes of different patients ("inter"-eyes).Conclusions: Visual function between fellow eyes showed a fair to moderate correlation that was statistically significant. The pattern of vision loss was also more similar in fellow eyes than between eyes of different patients. These results may help allow better prediction of visual outcome for the second eye in patients with NAION. These findings may also be useful for evaluating efficacy of therapeutic interventions.

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Introduction & Objectives: Surgery remains the treatment of choice for localized renal cell neoplasia. While radical nephrectomy was long considered as gold standard, partial nephrectomy (PN) has widened its indications over the past twodecades and has shown oncological results equivalent to radical nephrectomy for small tumors. Moreover, it is considered superior to radical nephrectomy in terms of non-cancer related mortality. The role of negative surgical margin has been widely debated. Intraoperative frozen section analysis has been shown to be unreliable, expensive, time-consuming and not well correlated to final pathology. The goal of the present study was to assess the correlation of intraoperative exvivo ultrasonographic (US) evaluation of resection margin to definitive pathology in patients undergoing PN.Materials & Methods: An observational study was carried out in ours 2 institutions from February 2008 to October 2010. Patients undergoing PN for T1-T2 renal tumors were included. Ex vivo US evaluation was performed. Considering availability of US engine, not all consecutive eligible patients were included. PN was undertaken either by open surgery or laparoscopic access in a standardized technique. The "minimal healthy tissue margin" technique was applied. Once resected, the specimen was kept in a saline solution and US determination of tumor margins was performed. Sequential images were captured in order to evaluate the whole capsule.Results: Twenty-two patients (9 women, age 63±11 years[46-78]) were included in the present analysis. Open or laparoscopic PN was performed in 19 and 3 patients, respectively. Intraoperative ex-vivo US showed negative surgical margin in all cases except one, needing a complementary renal parenchyma resection. US duration ranged from 1 to 4 minutes, with a median time of 1 minute. Definitive histological analysis confirmed the presence of 3 angiomyolipoma, 15 clear cell carcinoma (11 pT1a,3 pT1b,1 pT2), 3 chromophobe carcinoma (1 pT1a,1 pT1b,1 pT2) and 1 pT1a type II papillary tumor. Mean tumor size was 3,4±2.1 cm [0,6-7,2]. Final pathology revealed R0 margins in all cases.Conclusions: Intraoperative ex-vivo US evaluation of resection margin in patients undergoing PN is feasible, time-efficient, well correlated to definitive pathological examination, and should be evaluated in further prospective trials.