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R Blesa

Publications and source records attributed to R Blesa.

At least 19 recordsLinked to original sources
PubMed2005

[Diagnostic value and test-retest reliability of the Blessed Dementia Rating Scale for Alzheimer's disease: data from the NORMACODEM project].

INTRODUCTION: This study aims to discover the criterion validity of the Blessed Dementia Rating Scale (BDRS) for the diagnosis of Alzheimer's disease. Different cut-off scores and corresponding diagnostic sensitivities and specificities were established. Test-retest reliability and internal consistency of the BDRS were also analyzed. METHODS SAMPLE: 451 subjects were studied (254 controls, 86 subjects with mild cognitive impairment and 111 patients with Alzheimer's disease). INSTRUMENTS: scores from different sections of the Blessed score were obtained. The global score (BBRS-Total) is the result of the sum of the three sections, A (changes in every day activities), B (changes in habits) and C (changes in personality). The sum of parts A and B (BDRS-Mod) were also quantified. STATISTICS: ROC curves, intraclass correlation coefficient and Cronbach's alpha. RESULTS: The best cut-off score for the BDRS-Total was 3.5 (sensitivity: 87.39%, and specificity: 90%). For the BDRS-Mod, the best cut-off score was 1.5 (sensitivity: 90%, and specificity: 89%). Area under the ROC curve was 0.964 and 0.963 respectively. Intraclass correlation coefficient was 0.98 and Cronbach's alpha was 0.925. CONCLUSIONS: The BDRS has good discriminative validity in terms of sensitivity, specificity and predictive value. It also has good test-retest reliability and internal consistency.

Adult↗
PubMed2004

Neuropsychological markers of dementia in patients with memory complaints.

OBJECTIVES: To identify neuropsychological markers able to predict evolution towards dementia, through the detection of differential neuropsychological characteristics in a group of subjects complaining of memory loss, in a longitudinal, two-year follow-up study. METHODS: Longitudinal and retrospective comparisons of neuropsychological performance in: (a) subjects complaining of memory loss who, after a two-year period, met neurological and clinical diagnostic criteria for probable AD, and (b) subjects from the same group who did not progress towards dementia. A sample of 43 subjects were administered a comprehensive neuropsychological battery evaluating orientation, logical-verbal and visuoperceptive reasoning, immediate and delayed verbal and visual memory, attention, learning, executive functions and semantic and phonemic verbal fluency. RESULTS: Of the 43 subjects evaluated and then re-evaluated two years later, ten (23%) progressed to dementia according to the NINCS-ADRDA criteria for probable Alzheimer's disease. The neuropsychological performance of the rest of the subjects (n=33) over the two examinations was stable. In the retrospective analysis the principal differences between the two groups were found in the intensity of the initial memory deficits (WMS-R) and in the impairment of other cognitive areas in the dementia group: formation of concepts, vocabulary and similarities (WAIS), learning (WMS-R) and several executive functions. CONCLUSIONS: The deficits in cognitive areas other than memory are significant in subjects with memory complaints who progress towards dementia within two years. Memory complaints represent a risk factor that is at least as important as actual memory loss. Recent proposals for adding descriptive labels to the diagnosis of Mild Cognitive Impairment (MCI) in order to reflect the neuropsychological functions impaired in addition to memory (Petersen, 2001a), may be decisive from the prognostic viewpoint.

Aged↗
PubMed2003

Cholinesterase inhibitor rivastigmine enhance the mitochondrial electron transport chain in lymphocytes of patients with Alzheimer's disease.

Electron transport chain (ETC) dysfunction has been claimed to contribute to the expression of neurodegenerative disorders. We have investigated the effects of the treatment with rivastigmine, a commonly used cholinesterase inhibitor, on lymphocyte mitochondria of patients with Alzheimer's disease (AD). Increased enzymatic activities of diverse complexes and oxidative capacity of the ETC were found. Enhanced mitochondrial ETC function may contribute to the beneficial effects of rivastigmine on clinical manifestations of AD.

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PubMed2002

A novel mutation (V89L) in the presenilin 1 gene in a family with early onset Alzheimer's disease and marked behavioural disturbances.

A novel mutation (V89L) in the presenilin 1 (PSEN1) gene is described in a family with pathologically confirmed Alzheimer's disease. The mutation was identified in two affected members with early onset Alzheimer's disease characterised by early and marked behavioural disturbances. The mutation is located on the same side of the helix as other described mutations in the first transmembrane domain and its relation to other mutations in this helix suggests that they share a common pathogenic mechanism.

Alzheimer Disease↗
PubMed2002

Adaptation and standardization of the geriatric evaluation of relative's rating instrument (GERRI) for Spain.

BACKGROUND: The Geriatric Evaluation of Relative's Rating Instrument (GERRI) is a scale that evaluates the frequencies of alterations in behavior and functional capacity over a two-week period prior to exploration. The scale depends on the observations done by a relative o first caregiver of the studied subject. AIM: To adapt and standardize the GERRI for the use in the Spanish population as a part of a general project to standardized cognitive and functional tests. METHOD: The scale was administered to 444 subjects: 249 controls, 85 mild memory-cognitive disorders without dementia subjects (DWD) and 110 patients with Alzheimer-type dementia (ATD). An across-sectional statistical study was conducted in our samples stratified by age, gender and education. We evaluated the reliability of repeatability of the test, the internal reliability and the age, sex and education effects on the score of the different subscales. We also took into account the diagnostical validity in the Alzheimer disease and finally we correlated this test results with Mini mental test. RESULTS: The demographic variables age and schooling were found to affect the GERRI subscales differently. Gender did not reach significance. Internal consistency for the GERRI-Social, -Mood and -Cognitive were 0.8620, 0.7647 and 0.9259, respectively. CONCLUSION: The Spanish version of the GERRI may be applied to Spanish clinical series because of its reliable internal consistency and reproducibility.

Adult↗
PubMed2002

Asymmetric myoclonic parietal syndrome in a patient with Alzheimer's disease mimicking corticobasal degeneration.

We describe a patient who presented a progressive asymmetrical parietal syndrome including ideomotor apraxia, hemiinattention, unilateral limb dystonia and myoclonus. The clinical picture of this patient supported the clinical diagnosis of corticobasal degeneration (CBD). However, the neuropathologic examination revealed abundant cortical betaA4-amyloid deposits, and phosphorylated tau accumulation in neuritic plaques, neurofibrillary tangles and neuropil threads corresponding to Alzheimer's disease (AD) stage V of Braak and Braak. This case supports the clinical heterogeneity in AD and the existence of a clinical overlap between AD and CBD.

Alzheimer Disease↗
PubMed2001

A novel presenilin 2 gene mutation (D439A) in a patient with early-onset Alzheimer's disease.

The authors describe a novel missense mutation in the presenilin 2 (PSEN2) gene at residue 439 that predicts an aspartate-to-alanine substitution (D439A). This mutation was found in a 58-year old patient who displayed a progressive dementia at the age of 52. The mutation was absent in his cognitively normal relatives. Haplotype analysis indicated that his affected mother was the most probable mutation carrier. The D439A mutation is located near the C-terminal end of the PS2 protein, a region critical for endoproteolytic processing.

Alanine↗
PubMed2001

Detection of the presenilin 1 gene mutation (M139T) in early-onset familial Alzheimer disease in Spain.

In a family with early-onset Alzheimer disease (EOAD) from Spain we found a mutation in the presenilin 1 (PS1) gene that predicts a methionine-to-threonine change at the PS1 residue 139 (M139T). This mutation was previously reported in a independent French family. The age of onset of the disease was similar in the affected members from both families, suggesting a specific age of expression (range 47-50 years). The detection of the M139T mutation in an independent EOAD family strongly supports the pathogenicity of this mutation in familial Alzheimer disease (AD).

Alzheimer Disease↗
PubMed2001

Clinical validity of the 'mini-mental state' for Spanish speaking communities.

The Mini-Mental State (MMS) is a brief structured test of cognitive function. The purpose of this study was to adapt and normalise MMS for the Spanish population. The test was administered to 450 subjects (253 control volunteers, 86 mild memory/cognitive impairment without dementia subjects - CIWD and 111 Alzheimer's Disease patients - AD). A cross-sectional statistical study in a population stratified by age and education was conducted. A more accurate diagnosis is provided by scores that have been adjusted for age and level of education. The recommended cut-off in our study was 24/25 (non-demented above 24). The adaptation and normalisation of MMS provides the Spanish population with a highly valuable screening tool.

Adult↗
PubMed2001

Examination of motor output pathways in patients with corticobasal ganglionic degeneration using transcranial magnetic stimulation.

The alien hand sign (AHS) is often encountered in patients with corticobasal ganglionic degeneration (CBGD), revealing a unilateral dysfunction of the motor system of unknown pathophysiology. We examined the possibility of an abnormal cortical representation of hand muscles in 10 patients with probable CBGD and a prominent AHS. Cortical maps were obtained from the responses to magnetic stimuli applied with a figure of eight coil at an intensity of 110% above motor threshold. For comparison, the same study was carried out in 10 normal volunteers, eight patients with Parkinson's disease and eight patients with Alzheimer's disease. AHS patients had a larger extension of the cortical map to stimulation of the hemisphere contralateral to the AHS in comparison with the ipsilateral hemisphere. Furthermore, in six patients, focal stimulation of the hemisphere ipsilateral to the AHS gave rise to ipsilateral responses, delayed by a mean of 7.7 +/- 2.2 ms with respect to those recorded in the same muscle to contralateral stimulation. None of the other patients or control subjects had ipsilateral responses. Our results indicate an enhanced excitability, or reduced inhibition, of the motor area of the hemisphere contralateral to the AHS. The delay of the ipsilateral responses is compatible with a disinhibited transcallosal input.

Aged↗
PubMed2000

A novel presenilin 1 mutation (Leu166Arg) associated with early-onset Alzheimer disease.

BACKGROUND: Pathogenic mutations in the presenilin 1 (PS1) gene leading to early-onset Alzheimer disease have been described in various populations. The different mutations are not distributed randomly in the PS1 protein but are clustered in some PS1 exons. OBJECTIVE: To screen the PS1 gene in search of a potential mutation in a Spanish family with early-onset Alzheimer disease. METHODS: Single-stranded conformational polymorphism and heteroduplex analyses of all exons were used to search for a potential mutation. Subsequent sequencing of the DNA samples with an abnormal heteroduplex pattern was performed to identity the mutation in the sense strand and in the complementary strand. RESULTS: We found a novel mutation in exon 6 of the PS1 gene at a site that, so far, had not been described as a cluster of mutations. The mutation (an A to C change) causes a substitution of leucine for arginine at position 166 of the PS1 protein and is located adjacent to the transmembrane domain III, where few mutations have been found. In this family, the disease follows an autosomal inheritance pattern with early onset (range, 32-44 years). CONCLUSION: A novel missense mutation (Leu166Arg) at an atypical site associated with early-onset Alzheimer disease has been identified in a Spanish family.

Adult↗
PubMed2000

Galantamine: therapeutic effects beyond cognition.

Decline in cognitive function, especially memory, is the core feature of Alzheimer's disease (AD). However, other characteristic aspects of the disease are also important. These include patients' activities of daily living (ADL), including quality of sleep, behavioural disturbances and the impact of the disease on the caregiver. Therefore, increasing attention is being paid to clinically meaningful outcome measures, such as the Disability Assessment for Dementia (DAD) scale, the Neuropsychiatric Inventory (NPI), caregiver time and the Pittsburgh Sleep Quality Index (PSQI). Galantamine is a new treatment for AD that combines modulation of nicotinic receptors with inhibition of acetylcholinesterase. The present review outlines the positive and sustained effects of this agent on patients' behaviour and daily functioning as well as on caregiver time. In studies of up to 5 months' duration, galantamine-treated patients had a significantly better outcome on ADL than placebo-treated patients, and after 12 months of treatment with galantamine, patients' functional ability was preserved. Galantamine also significantly benefits behavioural disturbances in patients with AD. These functional and behavioural benefits are associated with a decrease in the burden on caregivers, as indicated by a reduction, relative to placebo, in the time spent supervising and assisting patients. These clinical benefits are not offset by disruption of patients' sleep, as has been reported with other cholinergic treatments.

Alzheimer Disease↗
PubMed2000

Significant association between the tau gene A0/A0 genotype and Parkinson's disease.

A significant association between the tau gene A0/A0 genotype and progressive supranuclear palsy has been reported recently. To determine if the presence of a tau polymorphism could constitute a risk factor for the development of sporadic and familial Parkinson's disease, a dinucleotide repeat marker at intron 11 was genotyped in 152 patients with PD, 52 patients with Alzheimer's disease, and 150 healthy controls. We detected a significant difference in A0 allelic frequency in the Parkinson's disease group (79.27%) compared with the control group (71%) and the Alzheimer's disease group (73.07%). Individuals homozygous for the A0 allele were also detected significantly more frequently in the Parkinson's disease group (63.8%) compared with the control group (52.66%) and the Alzheimer's disease group (48.07%). These results suggest a possible involvement of the tau gene in the pathogenesis of some cases of Parkinson's disease.

Aged↗
PubMed2000

[Neuroimaging of frontotemporal dementia].

With the development of neuroimaging, frontal lobe atrophy has been demonstrated with increased frequency, first with structural studies (computed tomography and magnetic resonance imaging), then with functional images (Single photon emission computed tomography and Positron emission tomography).

Dementia↗
PubMed1999

Identification of a novel polymorphism in the promoter region of the tau gene highly associated to progressive supranuclear palsy in humans.

An intronic polymorphism and other changes in the transcribed region of the tau gene forming a haplotype have been previously described associated to progressive supranuclear palsy (PSP). These results raised the possibility that a change at or near the tau gene could be responsible for an increased risk to develop PSP. We initiated the present work in research for potential changes in the promoter region of the tau gene that could further extend the previously described haplotype. The tau promoter region was analyzed through single strand conformation polymorphism followed by direct sequencing in PSP patients (n = 35), in controls (n = 195) and in Alzheimer's disease (AD; n = 74) patients. We have been able to identify a G to C change at position -221 of the tau gene promoter region. The CC genotype has been detected to be present with a significantly higher frequency in PSP patients (91.4%; P < 0.00001; OR = 11.8), but not in AD patients, as compared with controls (49.74%). Subsequently we have detected that the CC -221 tau promoter genotype is significantly associated to the tau intronic A0/A0 genotype (P < 0.00001). The detected -221 tau G to C change occurs within a potential c-myb proto-oncogene element present in the promoter region. Thus, in addition to extending the previously described haplotype associated to PSP, this -221 G to C change is an interesting candidate that could provide a potential explanation for the association of the haplotype to increased risk for developing PSP.

Base Sequence↗
PubMed1999

Dopamine receptor D2 intronic polymorphism in patients with Parkinson's disease.

An association between the intronic allele 3 of the dopamine receptor D2 (DRD2) gene and European Parkinson's disease (PD) cases has been reported recently. We initiated the present work in order to determine whether this association between the DRD2 locus and PD is also present in our population from Spain. The DRD2 gene polymorphism has been genotyped in 154 patients and in 125 controls. The allele 3 is present in 60.3% of the patients and in 55.2% of the controls. The genotype 3/3 is present in 36.3% of the patients and in 34.4% of the controls. No statistical differences in the genotype and allelic frequencies between the two groups have been found. No differences were also found when the patients were classified according to different criteria such as onset, family history, gender or clinical presentation. Thus our results do not support a role for the DRD2 locus to develop PD.

Adult↗
PubMed1999

Absence of p53 gene mutations in hepatocarcinomas from a Mediterranean area of Spain. A study of 129 archival tumour samples.

The incidence of p53 gene abnormalities in human hepatocellular carcinoma (HCC) varies in different geographical areas, being higher in regions where hepatitis virus infection and dietary exposure to aflatoxin B1 are the most common aetiological agents. These mutations are less frequently encountered in Europe, although some studies have reported p53 protein overexpression in up to 45% of cases analysed. We have analysed 129 tumour samples of primary malignant hepatic neoplasms recovered from paraffin blocks processed in two pathology laboratories in a Mediterranean area of Spain (Valencia and Gerona). Among 14 cases in which p53 immunohistochemistry expression proved positive, 5 stained in more than 50% of the cell nuclei. By PCR-SSCP analysis we could detect the complete sequence from exon 5 through 8 in 70 cases and part of this region in the remaining cases, but no mutations were found. We found no relationship with the clinical stage, tumour stage or clinical outcome. We conclude that p53 gene alterations are not a major event in the malignant transformation of hepatic cells in this region of the Mediterranean. The variable incidence of p53 gene alterations in other geographical areas may reflect a different genetic background for the aetiology of HCC.

Aged↗