17 research outputs found

    An hybridization of global-local methods for autonomous mobile robot navigation in partially-known environments

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    This paper deals with the navigation problem of an autonomous non-holonomic mobile robot in partially-known environment. In this proposed method, the entire process of navigation is divided into two phases: an off-line phase on which a distance-optimal reference trajectory enables the mobile robot to move from an initial position to a desired target which is planned using the B-spline method and the Dijkstra algorithm. In the online phase of the navigation process, the mobile robot follows the planned trajectory using a sliding mode controller with the ability of avoiding unexpected obstacles by the use of fuzzy logic controller. Also, the fuzzy logic and fuzzy wall-following controllers are used to accomplish the reactive navigation mission (path tracking and obstacle avoidance) for a comparative purpose. Simulation results prove that the proposed path planning method (B-spline) is simple and effective. Also, they attest that the sliding mode controller track more precisely the reference trajectory than the fuzzy logic controller (in terms of time elapsed to reach the target and stability of two wheels velocity) and this last gives best results than the wall-following controller in the avoidance of unexpected obstacles. Thus, the effectiveness of our proposed approach (B-spline method combined with sliding mode and fuzzy logic controllers) is proved compared to other techniques

    A Rare Case of Hypophosphataemic Osteomalacia in von Recklinghausen Neurofibromatosis

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    Background: Neurofibromatosis type 1 (NF1), also known as von Recklinghausen disease, is a one of the more common hereditary autosomal disorders. However, osteomalacia in neurofibromatosis type 1 is very rare tumour-induced osteomalacia; fibroblast growth factor-23 is usually implicated.Patients and methods: We report the case of a patient with a history of von Recklinghausen neurofibromatosis who presented with hypophosphataemic osteomalacia.Results: The patient was treated with high-dose calcitriol and oral phosphate with clinical improvement. Conclusion: Even though it is a rare entity, we must consider the diagnosis of hypophosphataemic osteomalacia in patients with neurofibromatosis in order to deliver appropriate treatment

    Osteogenesis imperfecta and Ledderhose disease: Is there a link? A report of two Tunisian siblings

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    Introduction: Osteogenesis imperfecta (OI) or “brittle bone disease” is a rare genetic disorder tissue due to an abnormal production of type I collagen. It can cause hearing loss, dentinogenesis imperfecta, heart failure, spinal cord problems and permanent deformities. Ledderhose’s disease or Plantar fibromatosis (PF) is also a rare condition that may be caused by an abnormal proliferation of collagen tissue. It is a benign fibroblastic proliferative disorder in which fibrous nodules may develop in the plantar aponeurosis, more specifically on the medial plantar side of the foot arch and on the forefoot region. Rare cases of association of polyfibromatosis with keloids or arthritis have been reported. Case report: We report two Tunisian brothers aged 17 and 14 years old, from a first-degree consanguineous marriage and with medical history of multiple bone fractures. The elder brother has medical history of juvenile arthritis treated with methotrexate and etanercept. Clinical examination of both patients showed blue sclera, bone deformities with humeral and femoral curvature and unequal leg length. They were diagnosed with OI and received bisphosphonate to prevent further fractures. One year later, they developed lumps under the sole skin of their feet. They were diagnosed with PF and received conservative treatment including non-steroidal anti-inflammatory drugs, physiotherapy and orthotic support. Conclusion: To the best of our knowledge, the association of PF with OI has never been reported. Both diseases suggest an association with abnormalities involving collagen. A question remains currently with no answer: is it a fortuitous association

    The CRP level and STATE score predict survival in cirrhotic patients with hepatocellular carcinoma treated by transarterial embolization

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    International audienceBackground: Prognostic biomarkers are needed in a heterogeneous population of patients with intermediate hepatocellular carcinoma (HCC) treated by transarterial (chemo)embolization. We aimed to validate the prognostic value of serum CRP levels and the STATE score, combining CRP, albumin and tumor burden.Methods: All cirrhotic patients with HCC treated by a first transarterial (chemo)embolization (2007-2013) in our institution were included. Overall survival was assessed using the Kaplan-Meier method, log rank, univariate and multivariate Cox analyses.Results: Among 157 patients included, 87% were men, 86% had Child Pugh A. Etiologies of liver disease included alcohol (57%), hepatitis C (32%), hepatitis B (11%) and/or metabolic syndrome (32%); 89% of patients were classified BCLC B. 33% of the patients had a CRP >1mg/dl and 33% a STATE score conferring poor prognosis (1mg/dl (20 vs. 8 months, P=0.00186). Median overall survival was 6.73 months for patients with a STATE score <18 vs. 22.23 months for patients with STATE-score ≥18 (P=0.0002). In multivariate analysis, a STATE score <18 was independently associated with increased mortality (HR: 2.06 (CI95%: 1.28-3.34), P=0.0031).Conclusion: In cirrhotic patients with HCC who underwent transarterial treatment, serum CRP level and STATE score at baseline can predict overall survival

    The CRP level and STATE score predict survival in cirrhotic patients with hepatocellular carcinoma treated by transarterial embolization

    No full text
    International audienceBackground: Prognostic biomarkers are needed in a heterogeneous population of patients with intermediate hepatocellular carcinoma (HCC) treated by transarterial (chemo)embolization. We aimed to validate the prognostic value of serum CRP levels and the STATE score, combining CRP, albumin and tumor burden.Methods: All cirrhotic patients with HCC treated by a first transarterial (chemo)embolization (2007-2013) in our institution were included. Overall survival was assessed using the Kaplan-Meier method, log rank, univariate and multivariate Cox analyses.Results: Among 157 patients included, 87% were men, 86% had Child Pugh A. Etiologies of liver disease included alcohol (57%), hepatitis C (32%), hepatitis B (11%) and/or metabolic syndrome (32%); 89% of patients were classified BCLC B. 33% of the patients had a CRP >1mg/dl and 33% a STATE score conferring poor prognosis (1mg/dl (20 vs. 8 months, P=0.00186). Median overall survival was 6.73 months for patients with a STATE score <18 vs. 22.23 months for patients with STATE-score ≥18 (P=0.0002). In multivariate analysis, a STATE score <18 was independently associated with increased mortality (HR: 2.06 (CI95%: 1.28-3.34), P=0.0031).Conclusion: In cirrhotic patients with HCC who underwent transarterial treatment, serum CRP level and STATE score at baseline can predict overall survival

    Brain magnetic resonance imaging findings in adult patients with congenital adrenal hyperplasia: Increased frequency of white matter impairment and temporal lobe structures dysgenesis

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    Background: Congenital adrenal hyperplasia (CAH) is an inherited recessive disorder of adrenal steroidogenesis. The enzymes most commonly affected are 21-hydroxylase. Past reports suggested brain magnetic resonance imaging (MRI) abnormalities in CAH patients, affecting white matter signal, temporal lobe and amygdala structure and function. Aims: In the present study, we aimed to investigate the frequency of white matter changes and temporal lobes structures dysgenesis in a population of patients having CAH due to 21-hydroxylase deficiency. Materials and Methods: Neurological examination and brain MRI were performed in 26 patients. Results: Neurological examination revealed mental retardation in three patients, tremor in two patients, tendon reflexes asymmetry in one patient, and cerebellar syndrome in one patient. Eleven patients (42.3%) showed MRI abnormalities: Eight of them had white matter hyperintensities, one patient had moderate atrophy in the right temporal, and hippocampal dysgenesis was found in the remaining two patients. Conclusions: Brain MRI abnormalities in CAH patients include white matter hyperintensities and temporal lobe structures dysgenesis. The mechanisms involved seem related to hormonal imbalances during brain development and exposure to excess exogenous glucocorticoids. Clinical implications of such lesions remain unclear. More extensive studies are required to define better the relationships between brain involvement and different CAH phenotypes and treatment regimens
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