PubMed Health⌕ Search

Biomedical subjects

Z Katsarou

Publications and source records attributed to Z Katsarou.

At least 19 recordsLinked to original sources
PubMed2004

Auditory event-related potentials in Parkinson's disease in relation to cognitive ability.

Auditory event-related potentials were evaluated in 45 nondemented patients with mild to moderate Parkinson's disease and 40 matched normal controls. All patients were neuropsychologically assessed by means of the Raven Colored Progressive Matrices, four subtests of the Wechsler Memory Scale (Digit Span Forward, Logical Memory, Visual Memory, Associate Learning), and the Wisconsin Card-sorting Test. The P300 component of the auditory event-related potentials was significantly prolonged in the patients with Parkinson's disease. Correlations between P300 latency and neuropsychological measures showed significant associations with lower performance on the Raven Colored Progressive Matrices and the Wisconsin Card-sorting Test. Our results indicate that for patients with mild to moderate Parkinson's disease subtle changes in cognitive abilities may be reflected as P300 prolongation.

Adult↗
PubMed2001

Clinical features of parkinsonian patients with the alpha-synuclein (G209A) mutation.

The motor and neuropsychological abnormalities in eight Greek patients with Parkinson's disease (PD) carrying the alpha-synuclein gene mutation (G209A) were studied. These patients (five men, three women) belonged to six different families. Their symptoms started between 32-50 years of age (mean +/- SD, 39.7 +/- 7.6 years) and they had a mean disease duration of 5.4 +/- 2.1 years (range, 2-9 years) at the time of examination. Rigidity and bradykinesia predominated both at disease onset as well as in the later stages and rest tremor was relatively uncommon. Neuropsychological assessment showed that one patient was mildly demented while another had impairment in memory, visuoconstructive abilities, and executive function. Depression was present in only one patient. Our findings indicate that genetic forms of parkinsonism share common motor and cognitive characteristics with sporadic PD but raise the possibility that greater cognitive impairment and the relative rarity of tremor may be distinctive features worthy of further investigation.

Adult↗
PubMed2001

Quality of life in Parkinson's disease: Greek translation and validation of the Parkinson's disease questionnaire (PDQ-39).

The Parkinson's disease questionnaire (PDQ-39) is a well-validated British scale for the assessment of health-related quality of life (HQoL) in Parkinson's disease (PD). The PDQ-39 has been translated into Greek and it was applied to 119 Greek PD patients. These patients were classified in stages according to the Hoehn and Yahr (HY) scale and their motor disability was assessed by means of the Unified Parkinson's disease rating scale (UPDRS) as well as the Schwab and England activities of daily living scale (ADL). The Beck depression inventory (BDI) was applied for the evaluation of depression. The translated version of PDQ-39, designated PDQ-39GrV, was validated as follows: (1) Cronbach's alpha coefficient and item-total Spearman's rank-order correlations were calculated in order to estimate the internal consistency of PDQ-39GrV scales. (2) Validity of the PDQ-39GrV was examined in terms of agreement with the clinical assessment parameters (stage, UPDRS. ADL and BDI scores). (3) Sixty one PD patients were re-evaluated 3-7 days later in order to check test-retest reliability. The results showed the following: (1) The PDQ-39GrV demonstrated very good internal consistency (alpha 0.71-0.94). Item-total correlations were statistically significant (r: 0.52-0.93). Test-retest measurements correlated significantly (p = 0.001). (2) Clinically obtained motor parameters correlated well with PDQ-39GrV scales influenced by physical aspects of the disease, while emotionally and socially influenced ones correlated with depression. Our findings indicate that PDQ-39 GrV is a reliable, easy to administer scale for the assessment of HQoL in Greek PD patients.

Activities of Daily Living↗
PubMed2001

Concurrent validity of the Test of Nonverbal Intelligence in Parkinson's disease patients.

The Test of Nonverbal Intelligence (TONI-2; L. Brown, R. J. Sherbenou, & S. Johnsen, 1990) and Raven's Colored Progressive Matrices (RCPM; J. C. Raven, 1965) are defined as language-free measures of cognitive ability. The purpose of the present study was to investigate the relation between the RCPM and the TONI-2 for samples of patients with Parkinson's disease (n = 75) and controls (n = 47). A regression equation was computed to evaluate the relation of the RCPM scores to the TONI-2 quotient. Regression equation results indicate that there is a significant overlapping linear variance between the two measures in both patients and controls.

Aged↗
PubMed2000

Abnormality of N30 somatosensory evoked potentials in Parkinson's disease: a multidisciplinary approach.

PURPOSE OF THE STUDY: Assess the N30 component of median nerve somatosensory evoked potentials (SEPs) in patients with Parkinson's disease (PD) and correlate its parameters with the severity of the disease, general cognitive ability and regional cerebral blood flow (rCBF). PATIENTS AND METHODS: Twenty-three non-demented, non-depressed PD patients (at stage II and III of the disease) and 23 age- and education-matched normal controls were enrolled in the study. SEPs were elicited by median nerve stimulation. PD patients' cognitive ability was assessed by means of: 1) Raven's Colored Progressive Matrices (RCPM); 2) the Test of Non-Verbal Intelligence (TONI-2); and 3) the Wisconsin Card Sorting Test (WCST). The patients' rCBF was evaluated by HMPAO SPECT. RESULTS: There was no difference between SEP N30 latency in PD patients and controls (P > 0.05). The P20-N30 peak-to-peak amplitude was lower in PD patients bilaterally (P < 0.05), and the amplitude of N30-P40 was lower on the right side only (P < 0.05). A significant increase in the amplitude ratio P14-N20/P20-N30 was observed in PD patients (P < 0.05). The correlation of these findings with the clinical parameters of the disease, and notably motor signs, was not significant. Of the three neuropsychological tests only the RCPM showed a positive relation to right P20-N30 amplitude. Regression analysis between SEP parameters and rCBF showed a correlation of N30 amplitude with blood flow in parietal cortical areas, but not in frontal regions.

Aged↗
PubMed2000

Seizures as a presenting feature of late onset metachromatic leukodystrophy.

OBJECTIVES: We describe 2 patients with epilepsy as an early manifestation of late onset metachromatic leukodystrophy (MLD). METHODS AND RESULTS: The first patient presented with epileptic seizures at the age of 34 years while neurological and cognitive abnormalities appeared later. MRI findings were compatible with leukodystrophy and low levels of arylsulphatase-A activity confirmed MLD. The second patient developed epileptic seizures and behavioral disturbances at the age of 19 years. She remained stable and seizure free for 8 years. Afterwards she developed uncontrolled epileptic seizures and status epilepticus as well as neurological and cognitive impairment. Leukodystrophy was diagnosed by MRI findings and low levels of arylsulphatase-A activity were compatible with MLD. CONCLUSION: Our 2 cases postulate that epileptic seizures may be an early and prominent manifestation of late onset MLD.

Adult↗
PubMed1999

Wisconsin Card Sorting Test variables in relation to motor symptoms in Parkinson's disease.

The Wisconsin Card Sorting Test, a standard test for the assessment of executive function and free of a motor component, was employed for the assessment of 37 nondemented patients with idiopathic Parkinson's Disease and 37 matched normal controls. The symptoms of the patients were clinically assessed by means of the Unified Parkinson's Disease Rating Scale, which yielded scores for the cardinal symptoms of the disease as well as a total motor score. The Wisconsin Card Sorting Test was administered in all subjects in its original form (128 cards), and it was scored to yield 16 measures according to the instruction of the Wisconsin Card Sorting Test revised manual. Patients with Parkinson's Disease had significantly lower scores on the following test variables: number of trials administered, perseverative responses, percent perseverative responses, and failure to maintain set. The correlations between the last three variables and total motor score were statistically significant. Of the four cardinal symptoms of the disease, only rigidity correlated significantly with the number of perseverative responses and percent perseverative responses. These findings provide a clue that the lower performance of these patients on certain variables of the Wisconsin Card Sorting Test may be related to the process of the disease.

Female↗
PubMed1998

A longitudinal study of visuospatial discrimination in parkinsonian patients.

Visuospatial discrimination was evaluated longitudinally in 45 patients with idiopathic Parkinson's disease. 47 normal matched subjects served as controls. Visuospatial discrimination was assessed by means of a picture test with complex superimposed objects (Poppelreuter's test) at the beginning of the study as well as three years later. At initial evaluation the group with Parkinson's disease identified fewer objects than the control group and made more errors. Relations between performance on the visuospatial discrimination task and the main parameters of the disease were not statistically significant. At reevaluation, three years later on the same task, performance by the group with Parkinson's disease deteriorated. Longitudinal assessment of motor symptoms showed that disease progressed during the study period in 35 patients. Comparison of motor deterioration with performance on the visuospatial discrimination task showed no statistically significant relationship.

Cognition Disorders↗
PubMed1997

Deductive and inductive reasoning in Parkinson's disease patients and normal controls: review and experimental evidence.

In the present study, fifty-four subjects were tested; twenty-seven with idiopathic Parkinson's disease and twenty-seven normal controls matched in age, education, verbal ability, level of depression, sex and socio-economic status. The subjects were tested on eight tasks. Five of the tasks were the classic deductive reasoning syllogisms, modus ponens, modus tollendo tollens, affirming the consequent, denying the antecedent and three-term series problems phrased in a factual context (brief scripts). Three of the tasks were inductive reasoning, including logical inferences, metaphors and similes. All tasks were presented to subjects in a multiple choice format. The results, overall, have shown nonsignificant differences between the two groups in deductive and inductive reasoning, an ability traditionally associated with frontal lobes involvement. Of the comparisons performed between subgroups of the patients and normal controls concerning disease duration, disease onset and predominant involvement of the left and/or right hemisphere, significant differences were found between patients with earlier disease onset and normal controls and between bilaterally affected patients and normal controls, demonstrating an additive effect of lateralization to reasoning ability.

Adult↗
PubMed1993

Algorithmic and heuristic strategies in comprehension of complement clauses by patients with Parkinson's disease.

Language ability in patients with idiopathic Parkinson's disease (PD) and normal control subjects (NC) matched on age, sex, education and socioeconomic status (SES) was investigated. The two groups of subjects were tested on eight sentence types in Greek in the form of main and complement clause with eight matrix verbs. These matrix verbs were ask (ask information), promise (commissive meaning), tell1 (order, command) and tell2 (give information) in sentences with no semantic constraints, and confess, sell, trust and scold in sentences with semantic constraints (implicit causality). The results show that language ability, despite relative preservation is significantly impaired in PD patients as compared to that of NC. More specifically, syntax with semantic constraints was the most effective independent variable to classify PD patients and NC subjects into two distinct groups according to a Logistic Regression Analysis. To restrict the algorithmic process in sentence comprehension, PD patients seem to make use of the minimal distance principle (MDP) and the "experiencer constraint" heuristic strategies. Possible similarities in language behavior between PD patients and aphasics, in general, are suggested.

Aged↗
PubMed1991

Understanding of relational time terms before and after in Parkinsonian patients.

The role of the relational time terms before and after in language comprehension was investigated using patients with Parkinson's disease (PD) and normal controls (NC) in Greek. Results lead to the following four conclusions: (a) Comprehension by PD patients of before and after constructions displaying syntactic, semantic, and cognitive constraints equivalent to those of English is significantly different from that of NC matched on chronological age, sex, education, and socioeconomic status. (b) Before is better understood than after. (c) Syntactic variables, when semantic effects are partialed out, do not affect performance. The same is true of semantic effects when syntactic variables are partialed out. (d) Order of mention of events is a predominant source of errors when syntax and semantics are controlled. The data are discussed in relation both to findings with aphasics and to developmental results on the same time terms.

Aged↗
PubMed1991

Strategies in comprehension of relative clauses by parkinsonian patients.

Twenty patients with Parkinson disease (PD) and twenty normal control subjects (NC) matched on age, sex, education and socio-economic status (SES) were tested for comprehension of four types of relative clauses with complex thematic roles (syntax) and no semantic and pragmatic constraints (reversible) in a sentence-picture matching task. The results show a clear language impairment for PD patients compared to NC. Additional evidence from testing school children in grade 1 (G1) and grade 6 (G6) indicates that G1 children perform similar to PD patients and G6 children perform as high as NC. The overall picture of the findings suggests: (1) PD patients process sentences with complex thematic roles and semantic reversibility on a heuristic and not on an algorithmic basis, a type of behavior assumed to be associated with frontal lobe dysfunction; (2) PD patients display some patterns of language behavior similar to those observed in aphasics. Similarities in language behavior between PD patients and G1 children are discussed with regard to the "regression hypothesis" (Jacobson, 1968).

Aged↗
PubMed1989

Piribedil therapy in Parkinson's disease. Use of the drug in the retard form.

We conducted a 20-week nonblind study to evaluate the efficacy of piribedil in 30 patients with idiopathic Parkinson's disease (PD). Prior to the study 17 of these patients were under L-Dopa treatment alone or in combination with anticholinergics and/or amantadine, while 13 patients who had never taken L-Dopa were treated only with anticholinergics and/or amantadine, or were without any medication. Piribedil (in the retard form) was administered orally at a gradually increasing dose up to 200 mg daily, while previous antiparkinsonian medication remained unchanged. Twenty-five patients showed statistically significant improvement. Among the cardinal symptoms of parkinsonism, tremor responded the best. Depression also appeared to respond favorably. Our results indicate that piribedil may be a useful adjuvant in the treatment of PD.

Aged↗
PubMedDate not supplied

Clinical observations in early and late onset Parkinson's disease.

The present study compares 30 patients who developed idiopathic Parkinson's disease (PD) at the age of 48 years or younger and 47 patients who developed the disease at the age of 68 years or older. PD patients with early onset had rigidity and bradykinesia as the predominant features at onset and during the course of the illness. In contrast older onset patients exhibited more often tremor at the beginning while later in the course most of them developed the full triad of symptoms i.e. tremor-rigidity-bradykinesia. In spite of such differences the overall disability status did not differ between the two groups of patients. An additional observation was that the early onset patients were apter to show earlier and more often abnormal movements and response fluctuations related to the L-Dopa therapy.

Activities of Daily Living↗
PubMedDate not supplied

Focal experimental epilepsy in rabbits.

The present study aimed at producing a chronic model of focal epilepsy in rabbits. In group A (30 rabbits) 0.05 ml alumina gel was injected in the right sensorimotor cortex, while in group B (10 rabbits) normal saline was injected in the same region. The observation period lasted 70 days. All group A animals developed spontaneous focal or focal initiated seizures that continued throughout the study. The rate of seizures varied in different animals. Both interictal and ictal epileptiform activities were recorded in the ECoGs. Histological examination showed a typical alumina granuloma with gliotic reaction adjacent to the granuloma.

Aluminum Hydroxide↗
PubMedDate not supplied

Hashimoto's encephalopathy: clinical and laboratory findings.

We describe a patient with a clinical picture characterized by subacute onset of confusion, myoclonus, tremor and generalized convulsive seizures with a relapsing course, which was attributed to Hashimoto's encephalopathy. EEG and MRI were diffusely abnormal. High titers of antithyroid antibodies were detected in her serum. She responded well to corticosteroids and her condition remained good during a one-year follow-up.

Brain Diseases↗