501 research outputs found

    MODIFICATION OF CP-5 FUEL ASSEMBLIES FOR FUEL CAPSULE IRRADIATION EXPERIMENTS

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    BS>The standard vertical fuel tube assembly of the CP-5 research reactor was modified to permit diversion of heavywater coolant into the thimble for temperature-controlled irradiation experiments of capsules containing fuel specimens. The modification entailed revisions to the thimble, outer top shield plug and center shield plug. and helium sweep system. The modified thimble is provided with inlet actor flow system through the thimble cavity. The coolant in the thimble removes fission heat from the encapsulated samples introduced into the thimble cavity. Flow tests of the thimble were first performed on a flow stand, with final flow characteristics being determined in the reactor. A helium purge system was incorporated to remove dissociation gases trapped in the thimble cavity. Four configurations of capsules and capsule baskets were flow tested under conditions simulating operating flow conditions from 2- to 10-Mw reactor power. Irradiation capsules are now being satisfactorily operated in the modified thimbles at 2-Mw reactor power. (auth

    Intracameral Chemotherapy (Melphalan) for Aqueous Seeding in Retinoblastoma: Bicameral Injection Technique and Related Toxicity in a Pilot Case Study.

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    The anterior chamber has been shown by pharmacokinetic studies to represent a sanctuary never achieving a tumoricidal dose with the present administration routes, such as systemic, intra-arterial, or intravitreal injections. A novel intracameral chemotherapy technique is described to control aqueous seeding in a pilot unilateral group E retinoblastoma case with primary aqueous seeding. Anterior segment toxicity was carefully monitored. Control of the retinal tumor and vitreous seeding was achieved by intra-arterial and intravitreal chemotherapies. Sterilization of the aqueous was achieved after a first cycle of 7 melphalan injections in the anterior chamber, but relapse was noted 3.5 months later. This relapse was finally controlled with a second cycle of 6 intracameral injections targeting the posterior chamber. Corneal endothelial cell density remained stable over the injection period. Heterochromia and a progressive cataract developed, which required cataract surgery. At 5 years' follow-up, the patient is tumor free with normal vision (20/20 in both eyes), full binocularity, and no metastasis. The present bicameral injection technique appears to be safe and effective with limited toxicity. Melphalan-induced side effects were noted on the iris and lens but with no impact on the final visual function

    First-line intra-arterial versus intravenous chemotherapy in unilateral sporadic group D retinoblastoma: evidence of better visual outcomes, ocular survival and shorter time to success with intra-arterial delivery from retrospective review of 20 years of treatment.

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    The introduction of intra-arterial chemotherapy (IAC) as salvage treatment has improved the prognosis for eye conservation in group D retinoblastoma. The aim of this study was to compare the outcomes of consecutive patients with advanced unilateral disease treated with either first-line intravenous chemotherapy (IVC) or first-line IAC. This is a retrospective mono-centric comparative review of consecutive patients. Sporadic unilateral retinoblastoma group D cases treated conservatively at Jules-Gonin Eye Hospital and CHUV between 1997 and 2014. From January 1997 to August 2008, IVC, combined with focal treatments, was the primary treatment approach. From September 2008 to October 2014, IAC replaced IVC as first-line therapy. 48 patients met the inclusion criteria, receiving only either IAC or IVC as primary treatment modality. Outcomes of 23 patients treated by IVC were compared with those of 25 treated by IAC; mean follow-up was 105.3 months (range 29.2-218.6) and 41.7 months (range 19.6-89.5), respectively. Treatment duration was significantly shorter in the IAC group (p<0.001). Ten eyes in the IVC group underwent enucleation. Recordable visual acuity of the salvaged eyes was significantly better in the IAC group (0.9 vs 1.4 logarithm of the minimum angle of resolution, p<0.01). No extraocular disease, metastases or long-term systemic complications were observed in either group. The difference in the time frame between treatment groups had an impact on the availability of intravitreal chemotherapy treatment. Despite this, the results reported here imply that eyes treated with first-line IAC will have shorter treatment period, better ocular survival and visual acuity than first-line IVC

    Current Indications of Secondary Enucleation in Retinoblastoma Management: A Position Paper on Behalf of the European Retinoblastoma Group (EURbG).

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    Secondary enucleation (SE) puts an irreversible end to eye-preserving therapies, whenever their prolongation is expected to violate the presumed state of metastatic grace. At present, it must be acknowledged that clear criteria for SE are missing, leading to empiric and subjective indications commonly related to disease progression or relapse, disease persistence masking the optic nerve head or treatment-related complications obscuring the fundus view. This absence of evidence-based consensus regarding SE is explained by the continuously moving frontiers of the conservative management as a result of diagnostic and therapeutic advances, as well as by the lack of studies sufficiently powered to accurately stratify the risk of metastasis in conservatively treated patients. In this position paper of the European Retinoblastoma Group (EURbG), we give an overview of the progressive shift in the indications for SE over the past decades and propose guidelines to assist decision-making with respect to when SE becomes imperative or recommended, with corresponding absolute and relative SE indications. Further studies and validation of biologic markers correlated with the risk of metastasis are expected to set more precisely the frontiers of conservative management and thus consensual criteria for SE in the future

    Adult-onset autoinflammation caused by somatic mutations in UBA1:A Dutch case series of patients with VEXAS

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    Background: A novel autoinflammatory syndrome was recently described in male patients who harbored somatic mutations in the X-chromosomal UBA1 gene. These patients were characterized by adult-onset, treatment-refractory inflammation with fever, cytopenia, dysplastic bone marrow, vacuoles in myeloid and erythroid progenitor cells, cutaneous and pulmonary inflammation, chondritis, and vasculitis, which is abbreviated as VEXAS. Objective: This study aimed to (retrospectively) diagnose VEXAS in patients who had previously been registered as having unclassified autoinflammation. We furthermore aimed to describe clinical experiences with this multifaceted, complex disease. Methods: A systematic reanalysis of whole-exome sequencing data from a cohort of undiagnosed patients with autoinflammation from academic hospitals in The Netherlands was performed. When no sequencing data were available, targeted Sanger sequencing was applied in cases with high clinical suspicion of VEXAS. Results: A total of 12 male patients who carried mutations in UBA1 were identified. These patients presented with adult-onset (mean age 67 years, range 47-79 years) autoinflammation with systemic symptoms, elevated inflammatory parameters, and multiorgan involvement, most typically involving the skin and bone marrow. Novel features of VEXAS included interstitial nephritis, cardiac involvement, stroke, and intestinal perforation related to treatment with tocilizumab. Although many types of treatment were initiated, most patients became treatment-refractory, with a high mortality rate of 50%. Conclusion: VEXAS should be considered in the differential diagnosis of males with adult-onset autoinflammation characterized by systemic symptoms and multiorgan involvement. Early diagnosis can prevent unnecessary diagnostic procedures and provide better prognostic information and more suitable treatment options, including stem cell transplantation
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