103 research outputs found

    Osteolytic clear cell meningioma of the petrous bone occurring 36 years after posterior cranial fossa irradiation: Case report

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    Objective and importance While bone invasion and hyperostosis are frequent phenomena in meningiomas, primary intraosseous meningiomas are rare and their occurrence in the skull base is an extraordinary exception. Moreover, radiation-induced meningiomas represent a unique clinical dilemma given the fact that patients with these tumors had often received a prior full course of radiotherapy. Clinical presentation A 42-year-old man presented with a 3-month history of progressively worsening facial asymmetry. His medical history was consistent for a posterior cranial fossa irradiation at the age of 6 years for a non-confirmed brain stem tumor. On admission his Karnofsky performance status was graded as 50% and his neurological examination showed a complete right facial nerve paralysis and hearing impairment. Computed tomography and magnetic resonance imaging demonstrated an osteolytic tumor invading the whole right petrous bone without intracranial involvement. Intervention As the tumor reached the external auditory canal, a tissue sample was obtained locally. Pathological examination of the lesion identified a grade II clear cell meningioma and the patient was consequently addressed for an intensity modulated radiation therapy. His condition remained unchanged till the most recent follow-up examination, 8 months later. Conclusions To the best of our knowledge, a radiation induced osteolytic clear cell meningioma of the petrous bone has not been previously reported. As little literature exists regarding the use of adjuvant therapies for these tumors, intensity modulated radiation therapy remains an attractive treatment option in case of pervious irradiation and general status alteration

    Les cancers de l’orbite etude retrospective à propos de 31 cas

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    locorégionale rendant le traitement difficile et mutilant. Dans ce travail, nous rapportons notre expérience dans la prise en charge diagnostique et thérapeutique de ces tumeurs. Matériels et méthodes : Notre étude rétrospective a concerné 31 cas de cancers de l’orbite colligés sur 13 ans (1993- 2005). Tous les patients ont bénéficié d’un examen clinique complet, d’une imagerie du massif facial (TDM et/ou IRM) et d’une biopsie de la tumeur. Le traitement a été basé sur la chirurgie, la radiothérapie et/ou la chimiothérapie. Résultats : La symptomatologie clinique était dominée par les signes ophtalmologiques et les algies faciales. L’imagerie a montré dans tous les cas un processus expansif tissulaire à point de départ orbitaire, avec lyse osseuse orbitaire chez 16 patients (51,6%), une extension au massif facial chez 7 patients (22,6%), endocrâniennes chez 6 patients (19,4%) et des formes bilatérales atteignant les deux orbites dans 3 cas (9,7%) l’anatomopathologie montrait une prédominance des lymphomes malins non hodgkiniens (32,3%) et des carcinomes épidermoïdes (32,3%), suivis des rhabdomyosarcomes embryonnaires (19,4 %). Douze patients ont été traités par chirurgie et radiothérapie postopératoire, dix patients par une association radio-chimiothérapie, et neuf autres par une chimiothérapie néo-adjuvante. La survie globale était de 67,8% à 3 ans, 48,4% à 5 ans et 22,6% à 10 ans. Conclusion : Les cancers de l’orbite sont de mauvais pronostic. Un diagnostic précoce et un traitement radical et adapté au type histologique permet d’améliorer la survie et la qualité de vie chez les patients atteints de ces tumeurs.Mots-clés : Orbite, cancer, lymphome, carcinome épidermoïde, rhabdomyosarcom

    Adaptive Oblivious Transfer and Generalization

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    International audienceOblivious Transfer (OT) protocols were introduced in the seminal paper of Rabin, and allow a user to retrieve a given number of lines (usually one) in a database, without revealing which ones to the server. The server is ensured that only this given number of lines can be accessed per interaction, and so the others are protected; while the user is ensured that the server does not learn the numbers of the lines required. This primitive has a huge interest in practice, for example in secure multi-party computation, and directly echoes to Symmetrically Private Information Retrieval (SPIR). Recent Oblivious Transfer instantiations secure in the UC framework suf- fer from a drastic fallback. After the first query, there is no improvement on the global scheme complexity and so subsequent queries each have a global complexity of O(|DB|) meaning that there is no gain compared to running completely independent queries. In this paper, we propose a new protocol solving this issue, and allowing to have subsequent queries with a complexity of O(log(|DB|)), and prove the protocol security in the UC framework with adaptive corruptions and reliable erasures. As a second contribution, we show that the techniques we use for Obliv- ious Transfer can be generalized to a new framework we call Oblivi- ous Language-Based Envelope (OLBE). It is of practical interest since it seems more and more unrealistic to consider a database with uncontrolled access in access control scenarii. Our approach generalizes Oblivious Signature-Based Envelope, to handle more expressive credentials and requests from the user. Naturally, OLBE encompasses both OT and OSBE, but it also allows to achieve Oblivious Transfer with fine grain access over each line. For example, a user can access a line if and only if he possesses a certificate granting him access to such line. We show how to generically and efficiently instantiate such primitive, and prove them secure in the Universal Composability framework, with adaptive corruptions assuming reliable erasures. We provide the new UC ideal functionalities when needed, or we show that the existing ones fit in our new framework. The security of such designs allows to preserve both the secrecy of the database values and the user credentials. This symmetry allows to view our new approach as a generalization of the notion of Symmetrically PIR

    Contributing factors affecting the prognosis surgical outcome for thoracic OLF

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    The thoracic ossification of ligamentum flavum (OLF) is a disease that produces spastic paraparesis, and there are various factors that may affect the surgical outcome of thoracic OLF patients. The authors of this study treated 19 of these thoracic OLF patients from 1998 to 2002, and retrospectively reviewed the patients′ age, sex, symptom duration, involved disease level, preoperative clinical features, neurological findings, radiological findings, the other combined spinal diseases and the surgical outcomes. There were excellent or good surgical outcomes in 16 patients, but 3 patients did not improve after thoracic OLF surgery: this included 1 patient, whose motor function worsened after decompressive thoracic OLF surgery. The favorable contributing factors of surgical outcome in thoracic OLF are a short preoperative symptom duration, single-level lesion, and unilateral lesion type on CT axial scan. On the contrary, the poor prognostic factors are beak type lesion and intramedullary signal changes on T2-weighted sagittal MRI. The complete preoperative evaluation including radiologic findings will provide valuable aid in presuming the surgical outcome for the thoracic OLF patients.ope

    Evidence for Widespread Genomic Methylation in the Migratory Locust, Locusta migratoria (Orthoptera: Acrididae)

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    The importance of DNA methylation in mammalian and plant systems is well established. In recent years there has been renewed interest in DNA methylation in insects. Accumulating evidence, both from mammals and insects, points towards an emerging role for DNA methylation in the regulation of phenotypic plasticity. The migratory locust (Locusta migratoria) is a model organism for the study of phenotypic plasticity. Despite this, there is little information available about the degree to which the genome is methylated in this species and genes encoding methylation machinery have not been previously identified. We therefore undertook an initial investigation to establish the presence of a functional DNA methylation system in L. migratoria. We found that the migratory locust possesses genes that putatively encode methylation machinery (DNA methyltransferases and a methyl-binding domain protein) and exhibits genomic methylation, some of which appears to be localised to repetitive regions of the genome. We have also identified a distinct group of genes within the L. migratoria genome that appear to have been historically methylated and show some possible functional differentiation. These results will facilitate more detailed research into the functional significance of DNA methylation in locusts

    Increased 30-Day Mortality in Very Old ICU Patients with COVID-19 Compared to Patients with Respiratory Failure without COVID-19

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    Purpose: The number of patients ≥ 80 years admitted into critical care is increasing. Coronavirus disease 2019 (COVID-19) added another challenge for clinical decisions for both admission and limitation of life-sustaining treatments (LLST). We aimed to compare the characteristics and mortality of very old critically ill patients with or without COVID-19 with a focus on LLST. Methods: Patients 80 years or older with acute respiratory failure were recruited from the VIP2 and COVIP studies. Baseline patient characteristics, interventions in intensive care unit (ICU) and outcomes (30-day survival) were recorded. COVID patients were matched to non-COVID patients based on the following factors: age (± 2 years), Sequential Organ Failure Assessment (SOFA) score (± 2 points), clinical frailty scale (± 1 point), gender and region on a 1:2 ratio. Specific ICU procedures and LLST were compared between the cohorts by means of cumulative incidence curves taking into account the competing risk of discharge and death. Results: 693 COVID patients were compared to 1393 non-COVID patients. COVID patients were younger, less frail, less severely ill with lower SOFA score, but were treated more often with invasive mechanical ventilation (MV) and had a lower 30-day survival. 404 COVID patients could be matched to 666 non-COVID patients. For COVID patients, withholding and withdrawing of LST were more frequent than for non-COVID and the 30-day survival was almost half compared to non-COVID patients. Conclusion: Very old COVID patients have a different trajectory than non-COVID patients. Whether this finding is due to a decision policy with more active treatment limitation or to an inherent higher risk of death due to COVID-19 is unclear.info:eu-repo/semantics/publishedVersio

    Intra-household agreement of urinary elemental concentrations in Tanzania and Kenya: potential surrogates in case–control studies

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    Element deficiencies and excesses play important roles in non-communicable disease aetiology. When investigating their roles in epidemiologic studies without prospective designs, reverse-causality limits the utility of transient biomarkers in cases. This study aimed to investigate whether surrogate participants may provide viable proxies by assessing concentration correlations within households. We obtained spot urine samples from 245 Tanzanian and Kenyan adults (including 101 household pairs) to investigate intra-household correlations of urinary elements (As, Ba, Ca, Cd, Co, Cs, Cu, Fe, Li, Mn, Mo, Ni, Pb, Rb, S, Se, Sr, Tl, V and Zn) and concentrations (also available for: Bi, Ce, Sb, Sn and U) relative to external population-levels and health-based values. Moderate-strong correlations were observed for As (r = 0.65), Cs (r = 0.67), Li (r = 0.56), Mo (r = 0.57), Se (r = 0.68) and Tl (r = 0.67). Remaining correlations were <0.41. Median Se concentrations in Tanzania (29 µg/L) and Kenya (24 µg/L) were low relative to 5738 Canadians (59 µg/L). Exceedances (of reference 95th percentiles) were observed for: Co, Mn, Mo, Ni and U. Compared to health-based values, exceedances were present for As, Co, Mo and Se but deficiencies were also present for Mo and Se. For well correlated elements, household members in East African settings provide feasible surrogate cases to investigate element deficiencies/excesses in relation to non-communicable diseases
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