Absence of cognitive, behavioral, or emotional dysfunction in progressive muscular atrophy.
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Biomedical subjects
Publications and source records attributed to S Abrahams.
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OBJECTIVES: To investigate longitudinally the profile of cognitive impairment in nondemented patients with ALS. METHODS: Twenty nondemented patients with ALS and 18 controls were interviewed at two time points separated by a 6-month interval. The extensive battery was designed to accommodate the range of physical disability present in ALS, and included measures of executive, memory, language, and visuospatial functions, everyday behavior, and emotion. RESULTS: On a test of simple word retrieval (Computerised Sentence Completion Test) patients with ALS became slower over time, while controls became faster at completing sentences with appropriate words. This effect remained when the analysis accommodated for progressive speech disability. Patients with ALS also displayed an impairment in both written and spoken verbal fluency indices (time to think of each word) at both time points, but there was no evidence of deterioration over time. On the Short Inventory of Minor Lapses, carers of patients with ALS displayed increased awareness of cognitive dysfunction in everyday behavior while controls' ratings of their partners decreased. In addition, patients displayed more depressive symptomology (although well below clinical levels) on the second interview vs controls. Patients with ALS also displayed emotional lability at both time points, although this did not increase over time. CONCLUSIONS: Cognitive deterioration in nondemented patients with ALS is a relatively slow process. Selective cognitive impairment in the form of verbal fluency deficits, most likely indicating executive dysfunction, appears relatively early on in the course of the disease, although language functions may become vulnerable as the disease progresses.
The current study sought to examine the performance of non-demented ALS patients on neuropsychological tests involving emotional perception and memory. Nineteen non-demented patients with ALS were compared with 20 healthy controls on assessments of facial expression recognition, social judgement ratings of faces and recognition memory for emotional words. Patients and controls were well matched to exclude a range of potentially confounding variables. The patients and controls demonstrated significant differences on only one test of cognitive functioning. The ALS group demonstrated a failure to show the normative pattern of enhanced recognition memory for emotional words compared to neutral words and produced higher scores than controls on recognition memory for neutral words. These findings suggest that patients with ALS show a different pattern of cognitive performance with respect to memory for emotional material when compared to healthy adults.
The cognitive impairment revealed in some non- demented amyotrophic lateral sclerosis (ALS) patients is characterized by executive dysfunction with widely repeated deficits on tests of verbal (letter) fluency. However, conflicting evidence exists of an impairment on other word retrieval tasks, such as confrontation naming, which do not place heavy demands on executive processes. Previous research has demonstrated intact confrontation naming in the presence of verbal fluency deficits, although naming deficits have been described in other studies. In this investigation, functional MRI (fMRI) techniques were employed to explore whether word retrieval deficits and underlying cerebral abnormalities were specific to letter fluency, which are more likely to indicate executive dysfunction, or were also present in confrontation naming, indicating language dysfunction. Twenty-eight non-demented ALS patients were compared with 18 healthy controls. The two groups were matched for age, intelligence quotient, years of education, and anxiety and depression scores. Two compressed-sequence overt fMRI activation paradigms were employed, letter fluency and confrontation naming, which were developed for use with an older and potentially impaired population. In ALS patients relative to controls, the letter fluency fMRI task revealed significantly impaired activation in the middle and inferior frontal gyri and anterior cingulate gyrus, in addition to regions of the parietal and temporal lobes. The confrontation naming fMRI task also revealed impaired activation in less extensive prefrontal regions, including the inferior frontal gyrus and regions of the temporal, parietal and occipital lobes. These changes were present despite matched performance between patients and controls during each activation paradigm. The pattern of dysfunction corresponded to the presence of cognitive deficits on both letter fluency and confrontation naming in the ALS group. This study provides evidence of cerebral abnormalities in ALS in the network of regions involved in language and executive functions. Moreover, the findings further illustrate the heterogeneity of cognitive and cerebral change in ALS.
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A novel cyclin, CycJ18, was isolated by complementation of G1 cyclin-deficient budding yeast with an Arabidopsis cDNA library. CycJ18 shares only 20% identity in its conserved cyclin box domain with other cyclins, and is predominantly expressed in young seedlings. CycJ18 is a member of a potential new plant cyclin class.
Genes and cDNAs for starch-branching enzyme II (SBEII) have been isolated from libraries constructed from Aegilops tauschii and wheat (Triticum aestivum) endosperm, respectively. One class of genes has been termed wSBEII-DA1 and encodes the N terminus reported for an SBEII from wheat endosperm. On the basis of phylogenetic comparisons with other branching enzyme sequences, wSBEII-DA1 is considered to be a member of the SBEIIa class. The wSBEII-DA1 gene consists of 22 exons with exons 4 to 21 being identical in length to the maize (Zea mays) SBEIIb gene, and the gene is located in the proximal region of the long arm of chromosome 2 at a locus designated sbe2a. RNA encoding SBEIIa can be detected in the endosperm from 6 d after flowering and is at its maximum level from 15 to 18 d after anthesis. Use of antibodies specific for SBEIIa demonstrated that this protein was present in both the soluble and granule bound fractions in developing wheat endosperm. We also report a cDNA sequence for SBEIIa that could arise by variant transcription/splicing. A second gene, termed wSBEII-DB1, was isolated and encodes an SBEII, which shows greater sequence identity with SBEIIb-type sequences than with SBEIIa-type sequences. Comparisons of SBEII gene structures among wheat, maize, and Arabidopsis indicate the lineage of the SBEII genes.
Neuropsychological investigations of amyotrophic lateral sclerosis (ALS) patients have revealed variable results on specific tests, despite a similar overall cognitive profile of predominantly executive dysfunction with some evidence of memory impairment. The most striking and consistent deficit is found using tests of verbal fluency. The current investigation explored why verbal fluency is particularly sensitive to the impairment in ALS, by investigating some of the underlying cognitive processes: (i) intrinsic response generation; (ii) phonological loop functions; and (iii) simple word retrieval. Twenty-two ALS patients and 25 healthy controls were investigated. The battery included: (i) written and spoken letter-based fluency, category fluency, design fluency; (ii) the Phonological Similarities effect and Word Length Effect; and (iii) computerised sentence completion and confrontational naming. The tests were designed to control for motor speed and to accommodate for the range of disabilities that are present in ALS patients. Significant impairments were found on some tests of intrinsic response generation, namely the Written Verbal Fluency Test, Category Fluency Test (generation of animal names) and Design Fluency Test. Phonological loop functions appeared to be intact with evidence of both the Phonological Similarities and Word Length Effects, but the ALS patients displayed significantly reduced working memory capacity. No deficits were found on tests of simple word retrieval. The findings indicate that verbal fluency impairments in ALS patients result from a higher order dysfunction, implicating deficits in the supervisory attentional system or central executive component of working memory, and are not caused or exaggerated by an impairment in phonological loop functions or in primary linguistic abilities. The study also demonstrates the importance of controlling for differences in motor speed, which may have served to exaggerate the presence of cognitive deficits in ALS patients reported by some other studies.
In an ALS Clinic, use of the Pathological Laughter and Crying Scale of Robinson et al. [Robinson RG, Parikh RM, Lipsey JR, Starkstein SE, Price TR. Pathological laughter and crying following stroke: validation of a measurement scale and double-blind treatment study. American Journal of Psychiatry 1993;150(2):286-293] revealed several problems: reliance on self-rating, insufficient period of assessment, inadequate exploration of 'appropriateness of emotion', lack of an item for abnormal smiling, amusement rather than happiness being the cause of laughter in ALS, and a frequency-based rating system. The necessary modifications produced a new Emotional Lability Questionnaire (ELQ) that was tested in 43 ALS patients and 43 healthy controls. The self-rated version of the ELQ was administered as a structured interview to each participant, and the independent-relationship between subscales of the ELQ for both versions, thus confirming its internal validity. Greater emotional lability appeared associated with pseudobulbar symptoms. The question why 14 patients rated themselves as severely labile in the crying domain alone and four in the laughter domain alone, required further study.
We have prepared mouse and rat hybridomas to a 43-kDa molecule expressed in the thymus, on a subpopulation of dendritic cells, and in the brain, in mammalian tissue derived from mouse, rat and human. Using CHO cells transiently transfected with adenovirus vector(s) expressing a cDNA construct for the relevant OX-2 gene, we show these monoclonal antibodies (Mabs) detect a molecule encoded by this construct (rat OX-2 (rOX-2), mouse OX-2 (mOX-2) and human OX-2 (huOX-2), respectively). Furthermore, at least some of the anti-rat Mabs detect determinants expressed on the murine OX-2 molecule, as we predicted in an earlier publication. Previous studies have implied that this molecule might serve an important role in regulation of cell signaling for cytokine production. Using one-way mixed leukocyte reactions we show that when cells are cultured in the presence of the species-specific Mab, cytokine production becomes polarized 'away from' type-2 cytokine production, with preferentially increased expression of type-1 cytokine production.
Forty-seven patients with unilateral temporal lobe epilepsy (TLE) were investigated on the Nine-Box Maze. The task was designed to compare working memory and spatial mapping theories of the functions of the hippocampus and provide measures of spatial, object, working, and reference memory. The results extended our previous findings in a larger group of patients. Spatial memory deficits across both working and reference memory conditions were found in patients with a right epileptogenic focus. There was no evidence of an object working memory deficit, but a nonlateralized impairment in object reference memory was revealed, which is consistent with our previous findings. The pattern of results was confirmed in a subgroup of 33 patients with unilateral atrophy localized to the hippocampus and parahippocampal gyrus, as verified by volumetric analysis of magnetic resonance images. In addition spatial memory errors significantly correlated with volumetric measures of mesial temporal lobe structures and not with measures of the remaining temporal cortex. In contrast, object reference memory errors correlated with volumetric measures of the temporal cortex and not with mesial temporal lobe structures. These findings support a specialized role for the right hippocampal region in spatial memory.
A lucerne (alfalfa, Medicago sativa) stem cDNA library was screened with a cinnamyl-alcohol dehydrogenase (CAD) cDNA probe from tobacco (Nicotiana tabacum cv. Samsun). Two distinctly different cDNA clones (54% identical) were isolated and identified as putative CAD-encoding cDNAs by comparison of their nucleotide sequences with those of CAD-encoding DNA sequences from other plant species. One of the cDNAs, MsaCad2, was found to be 99.4% identical at the nucleotide level to the previously isolated lucerne cad cDNA which encodes a CAD isoform involved in lignin biosynthesis. The other cDNA, MsaCad1, has not been reported previously in lucerne, and encodes a protein related to the ELI3 class of elicitor-inducible defence-related plant proteins. The MsaCad1- and MsaCad2-encoded proteins were expressed in Escherichia coli and CAD1 was shown to be active with a range of cinnamyl, benzyl and aliphatic aldehyde substrates, while CAD2 was specific for the cinnamyl aldehydes only. Each of the respective genes is present as one or two copies. The MsaCad1 gene is expressed most actively in stem and floral tissue, whereas MsaCad2 is most actively expressed in stem, hypocotyl and root tissue. In stem tissue, expression of both genes occurs predominantly in internodes 4 and 5 (from the apex). MsaCad2, in contrast to MsaCad1, is not significantly expressed in the top three internodes of the stem. Both MsaCad1 and MsaCad2 are wound-inducible, and the wound-responsiveness of each gene is modulated by salicylic acid.
Patients with unilateral temporal lobe damage resulting from intractable temporal lobe epilepsy (TLE, n = 30) or from temporal lobe resection (temporal lobectomy, TLR, n = 47) were investigated on the Nine-box Maze. The task, analogous to the radial arm maze, was designed to compare spatial mapping and working memory theories of the functions of the hippocampus. The task provides measures of spatial, object, working and reference memory, incorporated into a within subjects design. The spatial component was designed to encourage the formation of allocentric rather than egocentric spatial representations. Spatial memory deficits were found (across working and reference memory components) in both TLE and TLR patients with right temporal lobe damage, with intact spatial memory in patients with corresponding left temporal lobe damage. Performance on the matched non-spatial (object) working memory component was equal to healthy controls for all groups. However all patient groups showed a deficit on object reference memory. These findings are discussed in relation to the underlying temporal lobe pathology and particularly atrophy of the hippocampal formation. Overall, the results support the cognitive mapping theory of hippocampal function, with the demonstration of a selective (and probably allocentric) spatial memory deficit in patients with right hippocampal damage.
OBJECTIVES: To examine the relation between cognitive dysfunction and pseudobulbar features in patients with amyotrophic lateral sclerosis (ALS). METHODS: The performance of two patient groups, ALS with pseudobulbar palsy (n = 24) and ALS without pseudobulbar palsy (n = 28), was compared with 28 healthy age matched controls on an extensive neuropsychological battery. Tests used were the national adult reading test, short form of the WAIS-R, recognition memory test, Kendrick object learning test, paired associate learning, Wisconsin card sorting test, verbal fluency, Stroop and negative priming tests, a random movement joystick test, and a computerised Tower of Hanoi test. RESULTS: Tests of executive function showed a pronounced deficit on written verbal fluency in both ALS groups in comparison to controls, which tended to be more prominent in patients with ALS with pseudobulbar palsy. The random movement joystick test (a non-verbal test of intrinsic movement generation) showed an impairment in the generation of random sequences in patients with pseudobulbar palsy only. The computerised Tower of Hanoi showed a subtle planning impairment (shorter planning times) in all the patients with ALS compared with controls on trials requiring more complex solutions. In addition the pseudobulbar patients displayed shorter planning times on complex trials, and tended to solve these trials less accurately. There was also evidence of a deficit for all patients with ALS in comparison with controls on total errors and number of categories achieved on the Wisconsin card sorting test and a strong tendency towards an impairment on a task of selective attention and cognitive inhibition (negative priming). A word recognition memory deficit was showed across both ALS groups. CONCLUSIONS: This study elicited cognitive deficits (involving predominantly executive processes, with some evidence of memory impairment) in patients with ALS and further strengthened the link between ALS and frontal lobe dysfunction, this being more prominent in patients with pseudobulbar palsy. However, cognitive impairments suggestive of extramotor cortical involvement were not exclusive to this subgroup.
Genomic DNA fragments from Triticum tauschii (D-genome donor to wheat) carrying starch branching enzyme I (SBE I) type genes have been characterized. One fragment contains one complete gene and two partial genes in 16 kb of DNA. One of the partial genes is oriented in the opposite strand to the other two. The gene that is complete was sequenced. Its structure corresponds closely to that of rice in that exons 3-8 are retained at similar sizes and spacings. A cDNA closely corresponding to the complete gene was isolated and characterized; it codes for a putative protein that represents a novel type of SBE I, as it is shorter at the 3' end than the forms reported so far in other plants. A second genomic fragment contains a different SBE I gene. There appear to be approximately 10 copies of SBE I type genes in wheat (approximately 5 in T. tauschii) and most of them have been assigned to group 7 chromosomes. In situ hybridization indicates that a major locus for the genes is located at the distal end of the short arm of chromosome 7D.
The effect of oral amphetamine administration on the Kamin-blocking effect in healthy volunteer subjects was investigated. Against predictions, Kamin blocking was not disrupted by either a high or low oral dose of D-amphetamine under conditions which have, in previous studies, led to disruption of a related learning phenomenon (latent inhibition). This lack of effect of amphetamine administration upon Kamin blocking weakens hypotheses that this cognitive process is mediated by the same changes in dopaminergic activity which affect latent inhibition. Currently, the only data which show strong comparative associations between Kamin blocking and latent inhibition are when they are applied to schizophrenic populations. These results may suggest that Kamin blocking and latent inhibition may be measuring different aspects of schizophrenic cognitive dysfunction.
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PET measurements of regional cerebral blood flow (rCBF) were used to explore frontal lobe dysfunction in amyotrophic lateral sclerosis (ALS). An activation paradigm of executive frontal lobe function (verbal fluency), which contrasted rCBF during word generation and word repetition, was used. Two groups of ALS patients, defined by the presence or absence of cognitive impairment (ALSi) (impaired, n = 6: ALSu unimpaired, n = 6) were compared with healthy age-matched controls (n = 6). Patient selection was based on prior performance on a written test of verbal fluency. Additional neuropsychological assessment of the patients revealed evidence of executive and memory dysfunction in the ALSi group only, with marked deficits in tests of intrinsic generation. The ALSi patients displayed significantly (P < 0.001) impaired activation in cortical and subcortical regions including the dorsolateral prefrontal cortex (DLPFC; areas 46 and 9), lateral premotor cortex (areas 8 and 6), medial prefrontal and premotor cortices (areas 8 and 9), insular cortex bilaterally and the anterior thalamic nuclear complex. Although the three groups showed matched word generation performance on the scanning paradigm, the ALSu group displayed a relatively unimpaired pattern of activation. These results support the presence of extra-motor neuronal involvement, particularly along a thalamo-frontal association pathway, in some non-demented ALS patients. In addition, this study suggests dysfunction of DLPFC in some ALS patients with associated cognitive impairments.