Type 1 diabetes islet associated antibodies in subjects infected by echovirus 16.

AIMS/HYPOTHESIS: To determine whether the emergent infection by echovirus 16 that occurred in Cuba during the year 2000 was related to the presence of Type 1 diabetes associated autoantibodies. METHODS: The presence of ICA, IAA, GADA, IA2 antibodies and neutralizing antibodies (NtAb) to echovirus 16 were determined in sera from 38 infected children and adolescents and 80 control subjects, matched in sex, age, local residence and time of sample collection. RESULTS: The occurrence of a large-scale echovirus 16 epidemic was associated with the appearance of humoral autoimmune markers of Type 1 diabetes, especially for ICA, IAA and GADA. In the convalescent stage, ICA, IAA and GADA seroconversion was shown in 92.1%, 44.7% and 28.9% of echovirus 16 infected subjects. None of the 80 uninfected subjects had ICA or IAA, while one was GADA positive. ICA, IAA and GADA frequency was higher in the convalescent than in the acute stage (p<0.0005). A strong positive correlation was found between the NtAb to echovirus 16 and ICA titres in both acute and convalescent stage (r=0.91; p<0.0001, r=0.55; p=0.0003 respectively). CONCLUSION/INTERPRETATION: This work provides evidence of an association between echovirus 16 infection and the presence of Type 1 diabetes related antibodies (ICA, IAA and GADA). Our data show that the echovirus 16 infection might be capable of inducing a process of autoimmune beta-cell damage and support the hypothesis that enterovirus infections are important risk factors for the development of Type 1 diabetes.

Theory of mind and pragmatic abilities in dementia.

OBJECTIVE: "Theory of Mind" (ToM) is the capacity to attribute mental states to oneself and to others and to interpret behavior in terms of mental states. Deficits in both ToM and pragmatic abilities have been described in patients with neurologic disorders, such as frontal lobe lesions and right hemisphere strokes, but have not been assessed in demented patients. METHODS: This study examined ToM and pragmatic abilities in a consecutive series of 34 patients with probable Alzheimer disease (AD) using a second-order false belief story, 11 short stories assessing understanding of social situations, and a test of pragmatic abilities assessing both indirect requests and-conversational implications. RESULTS: Sixty-five percent of AD patients with mild dementia could not pass a second-order false belief task, whereas no failures were found in a group of 10 age-comparable healthy controls. AD patients who did not pass the second-order false belief task had more severe deficits on tests of verbal anterograde memory, verbal comprehension, abstract thinking, and naming, as compared with AD patients who passed the task. AD patients also showed significantly more severe pragmatic deficits than age-comparable healthy controls, and there was a significant association between ToM and pragmatic deficits. On the other hand, there were no significant associations between ToM or pragmatic deficits, and behavioral problems frequently reported in AD such as depression, delusions, apathy, and irritability. CONCLUSIONS: This initial exploratory investigation demonstrated significant deficits in both ToM and pragmatic abilities in a consecutive series of AD patients with mild dementia.

Remote memory in Alzheimer's disease.

The authors examined the severity and type of deficits in remote memory in patients with probable Alzheimer's disease (AD). In the first study, 40 AD patients showed significantly more severe deficits on both the free-recall and the recognition sections of the Remote Memory Scale (which measures memory for famous people and well-known events) compared with normal control subjects. In the second study, 25 AD patients showed significantly more deficits on the free-recall section of the Autobiographical Memory Scale compared with normal control subjects. Remote memory deficits in AD may be related to both retrieval deficits and damage to memory traces.

Explicit and implicit learning in patients with Alzheimer disease and Parkinson disease with dementia.

OBJECTIVE: To examine the differential impairment of implicit and explicit memory systems in cortical and subcortical dementias. BACKGROUND: Whereas verbal priming was reported to be impaired in patients with Alzheimer Disease (AD), patients with Parkinson Disease (PD) may be relatively more impaired on tasks of motor skill learning. METHODS: We examined 15 patients with Alzheimer disease, 10 patients with Parkinson disease and dementia (PD-D), 15 patients with PD but no dementia, and 24 age-comparable normal control subjects with a neuropsychologic battery that included tests of explicit memory (Buschke Selective Reminding Test, Benton Visual Retention Test, Digits Span), and tests of implicit memory (Word-Stem Completion task and the Maze Test). RESULTS: AD and PD-D groups showed similar deficits on all measures of explicit memory, and performed significantly worse than PD patients without dementia and normal control subjects. On the other hand, there were no significant between-group differences in any of the measures of implicit memory. CONCLUSIONS: Our study demonstrated preserved implicit learning in the context of severe explicit learning deficits in patients with dementia, but could not demonstrate a different profile of memory deficits between so-called cortical and subcortical dementias.

Neuropsychological correlates of apathy and depression in patients with dementia.

OBJECTIVE: To investigate the association between apathy and depression, and specific cognitive deficits in AD. BACKGROUND: Apathy and depression are frequent behavioral disorders in patients with AD. However, the neuropsychological correlates of these disorders have rarely been examined. METHODS: A comprehensive neuropsychological and psychiatric evaluation was carried out in 72 patients with AD with apathy and depression, 29 patients with AD with apathy only, 31 patients with AD with depression only, and 52 patients with AD with neither apathy nor depression (control group). RESULTS: Patients with apathy had significantly lower scores on tests of verbal memory, naming, set shifting, and verbal fluency compared with patients without apathy. The association of depression and apathy produced significantly more severe deficits compared with apathy only on a test of abstract thinking. Finally, depression in the absence of apathy was not associated with more severe cognitive impairments compared with the AD control group. CONCLUSIONS: Apathy, but not depression, is associated with significantly more severe frontal lobe related cognitive deficits in AD.

Prevalence and correlates of the catastrophic reaction in Alzheimer's disease.

We examined the prevalence of the catastrophic reaction (CR) in 146 patients with Alzheimer's disease. Sixteen percent showed a CR during the neuropsychological evaluation. A factor analysis of the CR scale demonstrated an anxious/angry factor that was significantly associated with higher irritability scores and a longer duration of illness, as well as a depressive factor that was significantly associated with more severe cognitive impairments and older age.

A randomized, double-blind, placebo-controlled study of methylphenidate in patients with organic amnesia.

We examined the usefulness of methylphenidate (MPH) in the treatment of organic amnesia in a randomized, double-blind, placebo-controlled design. Twenty patients with amnesia due to closed head injuries (n = 10), viral encephalitis (n = 2), stroke lesions (n = 4), or surgical brain resections (n = 4) were assessed with a neuropsychological battery after the intake of MPH (10, 20, 30 or 40 mg), or placebo. We found no significant benefit of MPH for any of the cognitive tests.Copyright Lippincott-Raven Publishers

Cognitive functions in major depression and Parkinson disease.

OBJECTIVE: To investigate the importance of major depression in the production of cognitive deficits in patients with Parkinson disease (PD). DESIGN: A comprehensive neuropsychological and psychiatric assessment was conducted in 19 patients with PD and major depression, 31 patients with PD without depression, 27 patients with major depression but without PD, and 12 age-comparable healthy controls. SETTING: Outpatient clinic. RESULTS: Patients with major depression (with or without PD) had significantly more severe cognitive deficits than both healthy controls and patients with PD without depression on tests of verbal fluency and auditory attention, while patients with PD and major depression had significantly more severe deficits on tasks of abstract reasoning and set alternation compared with the other 3 groups. CONCLUSIONS: Major depression in patients with PD is associated with significant deficits on specific cognitive tasks. While some of these deficits may be explained by the presence of major depression, frontal lobe-related cognitive impairments may result from an interaction between neuropathologic factors in PD and the mechanism of major depression.