A new distribution-free monitoring scheme based on ranks

In this article, we introduce a new nonparametric Shewhart − type control chart based on rank statistics. The setup of the proposed distribution − free monitoring scheme is presented in detail, while a real data example is studied in order to shed light on the implementation of the new control chart. Explicit formulae for the basic characteristics of the proposed rank-based chart are deduced. A detailed numerical study carried out depicts the performance of the new monitoring scheme for both in-control and out-of-control situations. © 2020 Taylor & Francis Group, LLC

Distribution-free monitoring schemes based on order statistics: a general approach

In this article, we establish a new class of distribution-free Shewhart-type monitoring schemes based on order statistics. The setup of the proposed family of nonparametric control charts is presented in detail. Specific monitoring schemes, already introduced in the literature, are confirmed to be members of the new class. In addition, a new nonparametric monitoring scheme that belongs to the class is established, while explicit formulae for its basic characteristics are reached. The numerical study carried out reveals that the proposed scheme achieves adversarial in-control and out-of-control performance. © 2019 Informa UK Limited, trading as Taylor & Francis Group

Patterns of depressive symptoms in epilepsy [Perfis de sintomas depressivos na epilepsia]

The purpose of this study was to determine the nature and extent of depressive symptoms among patients with epilepsy. Methods: Ninety patients were investigated over a three-month period: 42 were suffering from generalized epilepsy, 29 from focal epilepsy and 19 from undetermined epilepsy. All completed the Zung self-rating scale for assessment of the depressive symptoms. Results: Sixty-seven patients felt stigmatized because of epilepsy (67%): 73.6% in the undetermined epilepsy group, 55.1% in the focal epilepsy group and 88% in the generalized epilepsy group. Moreover, among the 90 epileptic patients studied, symptoms of irritability, indecisiveness, personal devaluation and emptiness showed a constant increasing trend for their presence from the undetermined epilepsy group through the generalized epilepsy group to the focal epilepsy group. Conclusions: These findings indicate that although the focal epilepsy patients felt less stigmatized, they did not differ greatly in terms of depressive symptoms, in relation to the undetermined epilepsy and generalized epilepsy patients

Trail Making Test error analysis in classic motor neuron disease

The use of non-traditional scores in neuropsychological assessment allows for pattern analysis of test performance, commonly referred to as Quantified Process Approach (QPA). In the present study, the QPA was taken to study error rates on the Trail Making Test (TMT) in 26 non-demented patients with classic motor neuron disease (cMND), who commonly present with impaired cognitive flexibility, and 26 matched healthy controls. Between-group comparisons revealed that cMND patients exhibited higher total error rates on the TMT Part B (TMT-B) relative to controls (p < 0.001), though no significant associations were noted between TMT errors and measures of attention and executive function obtained using the Stroop Neuropsychological Screening Test, the Wechsler Adult Intelligence Scale Digit Symbol and Digit Span subtests and the Wisconsin Card Sorting Test. Moreover, the percentage of cMND patients with normal TMT-B time-to-completion who committed at least one error (either sequential or perseverative errors) in TMT-B was significantly higher compared to controls (p = 0.005). These findings suggest that error analysis using the QPA may increase the clinical utility of TMT and should be considered in addition to time-to-completion scores, in the neuropsychological assessment of patients with cMND. © 2012 Springer-Verlag Italia

Structural MRI correlates of cognitive event-related potentials in multiple sclerosis

Purpose: Cognitive impairment in multiple sclerosis has been associated with cognitive event-related potentials and MRI abnormalities. This study aims to explore for the first time the association between P300 and MRI in multiple sclerosis. Methods: Fifty-eight relapsing-remitting patients (41.5 6 10.5 years old, 41 women, disease duration 139.7 6 84.9 months) and 51 healthy controls were used. Visual P300 responses and a set of 2- or 3-dimensional MRI indices were obtained. Neuropsychological testing and psychological evaluations were also performed. Results: Multiple sclerosis patients had significantly lower P300 amplitude and more prolonged P300 latencies and reaction times than healthy controls. In total, 67.2% of patients were identified with abnormal P300 response. These patients had greater disability and physical fatigue and had lower visuospatial memory scores than those with normal P300 response. Abnormally low P300 amplitude was associated with lower peripheral gray matter volume and was correlated only with normalized frontal horn width and normalized brain volume, after adjusting for age and education. The moderating role of brain reserve was also documented. Conclusions: P300 event-related potential was related to both linear and volumetric MRI markers. Future studies should expand these results in other disease types and longitudinally. Event-related potentials could serve as an ancillary tool for cognitive assessment in multiple sclerosis. Copyright © 2018 by the American Clinical Neurophysiology Societ

Periodic therapeutic plasma exchange in patients with moderate to severe chronic myasthenia gravis non-responsive to immunosuppressive agents: An eight year follow-Up

Few patients with moderate or severe myasthenia gravis (MG) do not respond to immunosuppressive treatment. We present our experience with periodic therapeutic plasma exchange (TPE), in 11 patients with MG resistant to intravenous immunoglobulin (IVIg) therapy, who had frequent relapses even whilst on high doses of immunosuppressive drugs, over a period of 8 years. All patients underwent TPE until control of their symptoms was achieved, and afterwards TPE sessions were continued periodically in an attempt to achieve remission of the disease, without immunosuppressant therapy. Two of the patients were progressively weaned off immunosuppressive agents, as well as TPE, and they are now symptom free. The other nine patients are still under a periodic TPE regime. Seven of them were weaned off all medications and required an average of 3.7 TPE sessions per year during the last 5 years. In the other two patients, those with the most severe form of the disease, the immunosuppressant dosage has been decreased and a TPE session every 2-3 weeks is required in order to control their symptoms. Through all these years TPE has been well tolerated and only minor side-effects were observed in two patients. Finally, during this 8 year follow-up period, nine of the patients treated with periodic TPE have been in good control of their symptoms over the last 5 years, and the other two patients live a normal life without any treatment in the last 3 years. Our results suggest that periodic TPE is safe and effective in the control of symptoms in patients with moderate to severe MG who do not respond to immunosuppressive therapies. © 2009 International Society for Apheresis

Neurocognitive impairment in whipple disease with central nervous system involvement

Young-onset dementias pose a major challenge to both clinicians and researchers. Cognitive decline may be accompanied by systemic features, leading to a diagnosis of "dementia plus" syndromes. Whipple disease is a rare systemic illness characterized by arthralgias, chronic diarrhea, weight loss, fever, and abdominal pain. Central nervous system involvement, including severe cognitive deterioration, may precede systemic manifestations, appear during the course of the disease, or even be the only symptom. We report a previously highly functional 48-year-old man whom we first suspected of having early-onset neurodegenerative dementia but then diagnosed with Whipple disease based on a detailed clinical and laboratory evaluation. Initial neuropsychological evaluation revealed marked impairment in the patient's fluid intelligence and severe cognitive deficits in his information processing speed, complex attention, memory, visuomotor and construction dexterities, problem solving, and executive functions. At neuropsychological follow-up 21 months later, his information processing speed had improved only slightly and deficits persisted in his other cognitive functions. Repeat brain magnetic resonance imaging at that time showed that he had responded to antibiotic treatment. Because Whipple disease can cause young-onset "dementia plus" syndromes that may leave patients with neurocognitive deficits even after apparently successful treatment, we recommend comprehensive neuropsychological assessment for early detection of residual and reversible cognitive processes and evaluation of treatment response. © 2014 by Lippincott Williams and Wilkins

Unusual cases of multiple symmetrical lipomatosis with neurological disorders

Multiple symmetrical lipomatosis (MSL) is a rare disorder of unknown etiology defined as the presence of multiple and symmetrical fatty accumulations, usually involving the upper trunk, neck and head. Frequently associated findings include diabetes mellitus, hyperlipidemia, liver disease, hypothyroidism and polyneuropathy of unknown origin, but nevertheless, there are published reports of cognitive disorders in patients with MSL. We describe two unusual cases (38-year-old and 45-year-old Greek men) of MSL who presented with polyneuropathy and memory disorders. This is the first description of memory disorders in patients with MSL. We propose that Mini-Mental State Examination and assessment of cognitive functions should be performed for all patients with MSL. The underlying mechanism in our patients remains unknown, and this question should be the subject of a future study. ©2009 Marshfield Clinic

Cognitive deficits presenting as psychiatric symptoms in a patient with moyamoya disease

The case of a midd le-aged man who had intraventricular hemorrhages second ary to Moyamoya disease (MMD), and initially, presented with psychiatric symptoms which did not respond to treatment is described. Neuropsychological assessment showed underlying significant cognitive deficits, mostly of complex attention and speed of information processing, visuospatial and constructional abilities, verbal and nonv erbal memory, and executive fun ctions. These deficits remained stable or slightly improved in follow-up assessments. Cognitive dysfun ction should be suspected in case of psychiatric or psychiatric-related symptoms in MMD patients. This case stud y in Greece highlights the range of preserved and impaired cognitive fun ctions in adu lt MMD by means of repeated neuropsychological evaluations in which a broad range of cognitive abilities were assessed. © Psychological Reports 2010