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1.
Disabil Rehabil ; 45(6): 1063-1078, 2023 03.
Article in English | MEDLINE | ID: mdl-35352609

ABSTRACT

PURPOSE: Primary progressive aphasia (PPA) is a language-led dementia associated with Alzheimer's pathology and fronto-temporal lobar degeneration. Multiple tailored speech and language interventions have been developed for people with PPA. Speech and language therapists/speech-language pathologists (SLT/Ps) report lacking confidence in identifying the most pertinent interventions options relevant to their clients living with PPA during their illness trajectory. MATERIALS AND METHODS: The aim of this study was to establish a consensus amongst 15 clinical-academic SLT/Ps on best practice in selection and delivery of speech and language therapy interventions for people with PPA. An online nominal group technique (NGT) and consequent focus group session were held. NGT rankings were aggregated and focus groups video recorded, transcribed, and reflexive thematic analysis undertaken. RESULTS: The results of the NGT identified 17 items. Two main themes and seven further subthemes were identified in the focus groups. The main themes comprised (1) philosophy of person-centredness and (2) complexity. The seven subthemes were knowing people deeply, preventing disasters, practical issues, professional development, connectedness, barriers and limitations, and peer support and mentoring towards a shared understanding. CONCLUSIONS: This study describes the philosophy of expert practice and outlines a set of best practice principles when working with people with PPA.Implications for rehabilitationPrimary progressive aphasia (PPA) describes a group of language led dementias which deteriorate inexorably over time.Providing speech and language therapy for people with PPA is complex and must be person centred and bespoke.This study describes the philosophy of expert practice and outlines a set of best practice principles for speech and language therapists/pathologists working with people with people with PPA.


Subject(s)
Aphasia, Primary Progressive , Language Therapy , Humans , Language Therapy/methods , Speech , Consensus , Aphasia, Primary Progressive/therapy , Philosophy
2.
Trials ; 20(1): 282, 2019 May 22.
Article in English | MEDLINE | ID: mdl-31118095

ABSTRACT

BACKGROUND: Leisure activities can be both enjoyable and cognitively stimulating, and participation in such activities has been associated with reduced age-related cognitive decline. Thus, integrating stimulating leisure activities in cognitive training programs may represent a powerful and innovative approach to promote cognition in older adults at risk of dementia. The ENGAGE study is a randomized controlled, double-blind preference trial with a comprehensive cohort design that will test the efficacy and long-term impact of an intervention that combines cognitive training and cognitively stimulating leisure activities. METHODS: One hundred and forty-four older adults with a memory complaint will be recruited in Montreal and Toronto. A particular effort will be made to reach persons with low cognitive reserve. Participants will be randomly assigned to one of two conditions: cognitive + leisure training (ENGAGE-MUSIC/SPANISH) or active control (ENGAGE-DISCOVERY). The ENGAGE-MUSIC/SPANISH training will include teaching of mnemonic and attentional control strategies, casual videogames selected to train attention, and classes in music or Spanish as a second language. The ENGAGE-DISCOVERY condition will comprise psychoeducation on cognition and the brain, low-stimulating casual videogames and documentary viewing with discussions. To retain the leisure aspect of the activities, participants will be allowed to exclude either music or Spanish at study entry if they strongly dislike one of these activities. Participants randomized to ENGAGE-MUSIC/SPANISH who did not exclude any activity will be assigned to music or Spanish based on a second random assignment. Training will be provided in 24 2-h sessions over 4 months. Outcomes will be measured at baseline, at 4-month follow-up, and at 24-month follow-up. The primary outcome will be cognitive performance on a composite measure of episodic memory (delayed recall scores for words and face-name associations) measured at baseline and at the 4-month follow-up. Secondary outcomes will include a composite measure of attention (speed of processing, inhibition, dual tasking, and shifting), psychological health, activities of daily living, and brain structure and function and long-term maintenance measured at the 24-month follow-up. Information on cognitive reserve proxies (education and lifestyle questionnaires), sex and genotype (apolipoprotein (Apo)E4, brain-derived neurotrophic factor (BDNF), and catechol-O-methyltransferase (COMT)) will be collected and considered as moderators of training efficacy. DISCUSSION: This study will test whether a program combining cognitive training with stimulating leisure activities can increase cognition and reduce cognitive decline in persons at risk of dementia. TRIAL REGISTRATION: NCT03271190 . Registered on 5 September 2017.


Subject(s)
Cognition , Leisure Activities , Memory Disorders/therapy , Randomized Controlled Trials as Topic , Activities of Daily Living , Aged , Aged, 80 and over , Attention , Brain/pathology , Brain/physiopathology , Cohort Studies , Double-Blind Method , Humans , Memory Disorders/psychology , Middle Aged , Outcome Assessment, Health Care , Research Design
3.
Chromosoma ; 112(7): 342-9, 2004 May.
Article in English | MEDLINE | ID: mdl-15138769

ABSTRACT

A multidisciplinary study was carried out to analyse the chromosome doubling process during the early stages of in vitro maize microspore embryogenesis. The main stages (microspore derivatives) that were formed in the course of the culture were analysed. Chromosome number was determined from squashed cells, and DNA content was measured by cytometry. In parallel, an ultrastructural analysis of the microspore derivatives demonstrated the occurrence of a nuclear fusion process. It seems likely that nuclear fusion ensures chromosome doubling at early stages of induced microspore embryogenesis. It occurs precisely at the 5/7 day stage in the embryonic domain and probably leads to polyploidy in the endosperm domain of the microspore derivatives. As a conclusion a scheme summarises the results and proposes an interpretation of the sequence of chromosome doubling events during early maize microspore embryogenesis. Understanding of this process will be important for future efforts to increase the percentage of homozygous plants for crop improvement.


Subject(s)
Cell Nucleus/ultrastructure , Chromosomes, Plant/genetics , Diploidy , Pollen/embryology , Zea mays/embryology , Zea mays/genetics , Cell Fusion , Cell Nucleus/metabolism , Cells, Cultured , Chromosomes, Plant/chemistry , Pollen/metabolism , Pollen/ultrastructure , Time Factors , Zea mays/ultrastructure
4.
Brain Cogn ; 49(2): 241-4, 2002 Jul.
Article in English | MEDLINE | ID: mdl-15259401

ABSTRACT

Semantic dementia is a commonly accepted term for a language disorder resulting from neurodegenerative changes due to frontotemporal dementia. An intervention program was designed to halt and/or decelerate the effects of progressive anomia in AK, a 63-year-old female with semantic dementia. Pictorial stimuli were selected and labeled with their respective names and a description most relevant to AK's experience. Daily homework assignments were carried out, during which AK looked at the picture, read the label aloud, and read the description. Positive short-term effects of treatment were observed on treated items.


Subject(s)
Anomia/etiology , Anomia/therapy , Association Learning , Dementia/complications , Verbal Learning , Dementia/therapy , Female , Humans , Middle Aged , Pilot Projects , Semantics , Vocabulary
5.
Planta ; 210(5): 749-57, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10805446

ABSTRACT

Egg cells were analysed cytologically during the female receptivity period in maize (Zea mays L., line A 188). Three classes of egg cell were distinguished: type A--small, non-vacuolated cells with a central nucleus; type B--larger cells with small vacuoles surrounding the perinuclear cytoplasm located in the middle of the cell; type C--big cells with a large apical vacuole and the mid-basal perinuclear cytoplasm. The less-dense cytoplasm of the vacuolated egg cells usually contained numerous cup- or bell-shaped mitochondria. The three egg types appear to correspond to three late stages of egg cell differentiation. The frequencies of each of the three egg types were monitored in developing maize ears before and after pollination. In young ears, with the silks just extending out of the husks, small A-type cells were found in about 86% of ovules. Their frequency decreased to about 58% at the optimum silk length, remained unchanged in non-pollinated ears, and fell to 16% at the end of the female receptivity period. However, after pollination and before fertilisation the frequency of these cells decreased to about 33%, and the larger vacuolated egg cells (types B and C) prevailed. At various stages of the receptivity period, pollination accelerated changes in the egg population, increasing the number of ovules bearing larger, vacuolated egg cells. Experiments with silk removal demonstrated that putative pollination signals act immediately after pollen deposition and are not species-specific.


Subject(s)
Cell Differentiation/physiology , Pollen/physiology , Zea mays/physiology , Microscopy, Electron , Reproduction , Seeds/cytology , Seeds/physiology , Seeds/ultrastructure , Time Factors , Zea mays/embryology , Zea mays/ultrastructure
6.
Brain Lang ; 72(3): 193-218, 2000 May.
Article in English | MEDLINE | ID: mdl-10764517

ABSTRACT

The narrative production of patients with Broca's aphasia and age-and education-matched control subjects was analyzed using the Quantitative Production Analysis (Saffran et al., 1989), a procedure designed to provide measures of morphological and structural characteristics of aphasic production. In addition to providing data for a larger number of subjects than in the original study, we provide data on interrater and test-retest reliability. The data were also submitted to factor and cluster analyses. Two factors characterized the data and the cluster analysis yielded four sets of patients who performed differently on these factors. In particular, there is evidence that agrammatic patients can differ in their production of free and bound grammatical morphemes, substantiating earlier claims in the literature.


Subject(s)
Aphasia, Broca/diagnosis , Verbal Behavior/physiology , Adult , Aged , Cluster Analysis , Factor Analysis, Statistical , Female , Humans , Linguistics , Male , Middle Aged , Reproducibility of Results , Time Factors
7.
J Speech Lang Hear Res ; 43(2): 395-413, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10757692

ABSTRACT

Patients with dementia of the Alzheimer's type (DAT) and age- and education-matched older volunteers were tested on a battery of working memory tests, as well as on two tests of sentence comprehension. Patients had reduced spans and impaired central executive processes in working memory but showed normal effects of phonological and articulatory variables on span. On the sentence comprehension tasks, DAT patients showed effects of the number of propositions in a sentence but not of syntactic complexity. Impairment in the central executive processes of working memory in DAT patients was correlated with the effect of the number of propositions in a sentence on the sentence comprehension tasks. The results suggest that patients with DAT have working memory impairments that are related to their ability to map the meanings of sentences onto depictions of events in the world.


Subject(s)
Alzheimer Disease/complications , Memory Disorders/diagnosis , Memory Disorders/etiology , Aged , Cognition , Female , Humans , Male , Neuropsychological Tests , Phonetics , Vocabulary
8.
Brain Lang ; 62(3): 361-97, 1998 May.
Article in English | MEDLINE | ID: mdl-9593615

ABSTRACT

Patients with dementia of the Alzheimer's type (DAT) and matched normal controls were given three tests of syntactic comprehension in which nonlinguistic visual and memory task demands were varied. In all tasks, subjects were presented spoken semantically reversible sentences with a variety of syntactic structures and required to match the sentence to a picture. In the first experiment, subjects matched the spoken sentence to one of two pictures that appeared either before or immediately following the presentation of the sentence. The target picture depicted the spoken sentence correctly and the foil depicted the reversed thematic roles to those in the sentence (i.e., it was a syntactic foil). The second experiment employed a sentence video-verification task in which subjects were required to determine if the spoken sentence matched a videotaped depiction of the action in the sentence or a syntactic foil. In the third experiment, in different conditions, subjects were required to determine whether the spoken sentence matched a single picture or to choose the picture that matched the sentence from an array of two or three pictures. In this experiment, both lexical and syntactic foils were used. In all tasks, DAT patients were affected by the number of propositions in the presented sentence, but not by the syntactic complexity of the sentence. Control subjects also were unaffected by the syntactic complexity of the sentence; the number-of-proposition effect was present in some experiments in the control population. Comparison of performance across the one-, two-, and three-picture versions of the task showed that the magnitude of the effect of number of propositions increased as the number of pictures in the array increased. In addition, analysis of the data from each of the tasks separately showed that the effect of number of propositions only occurred when subjects were attempting to match the target to a syntactic foil (one-picture version) or to choose between the target and a syntactic foil (two- and three-picture versions). The results support the view that patients with DAT do not have disturbances affecting syntactic processing. In addition, they suggest that the effect of number of propositions arises at a stage of analysis that is partially separate from assigning sentence meaning, such as in holding a representation of the sentence in memory until the pictures can be analyzed and encoded and/or in comparing the results of the picture analysis with a stored representation of the sentence meaning.


Subject(s)
Alzheimer Disease/complications , Language Disorders/diagnosis , Language Disorders/etiology , Aged , Aged, 80 and over , Analysis of Variance , Cognition Disorders/diagnosis , Cognition Disorders/etiology , Female , Humans , Language Tests , Male , Middle Aged , Neuropsychological Tests , Semantics , Severity of Illness Index
9.
Dev Biol ; 177(1): 190-203, 1996 Jul 10.
Article in English | MEDLINE | ID: mdl-8660887

ABSTRACT

We established conditions for the regeneration of natural maize zygotes isolated from pollinated plants with the goal of investigating the molecular control of early embryogenesis in higher plants. Viable zygotes were excised from embryo sacs by minimal enzymatic digestion and microdissection. Viable zygotes transferred to coculture with androgenic microspores from barley developed into embryo-like structures in 61% of the cases. No development was observed when zygotes were cultured in the presence of maize anthers undergoing androgenetic embryogenesis. Zygote-derived embryo-like structures regenerated into fertile plants through secondary embryogenesis when transferred to solid medium. The first zygotic division was asymmetrical and bipolar structures similar to pretransitional embryos observed in planta were later produced as observed using light and electron microscopy. Conditions for efficient microinjection of DNA into zygotes were established. Calcofluor and PATAG staining of zygotes showed that cell wall regeneration occurred as early as 20 min after enzymatic isolation and that after 2 hr, each zygote was bordered with cell wall material. Through quantitative microphotometry, DNA synthesis during the first cell cycle of the zygote was shown to occur between isolation and 12 hr of culture. Microinjection of two types of reporter genes (GUS gene and anthocyanin regulatory genes) demonstrates transient expression in plant zygotes. On average, 3.5% of microinjected zygotes showed transgenic expression. Reporter gene expression was observed in zygotes at different time points of their first cell cycle.


Subject(s)
Gene Expression Regulation, Plant , Zea mays/embryology , Zea mays/genetics , Zygote , Cell Cycle/physiology , Coculture Techniques , DNA, Plant/biosynthesis , Genes, Plant , Genes, Reporter/genetics , Microscopy, Electron , Transfection , Transgenes/genetics , Zea mays/growth & development , Zea mays/ultrastructure , Zygote/ultrastructure
10.
Plant Mol Biol ; 27(1): 105-13, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7865780

ABSTRACT

One hundred maize zygotic embryos microdissected at the transition stage were used to construct a cDNA library after non-selective PCR (NS-PCR) amplification of whole cDNA populations. The library contains 2.3 x 10(5) recombinants and two different calmodulin cDNAs were cloned using a heterologous probe from petunia. Calmodulin expression was confirmed throughout maize embryogenesis at the mRNA, amplified cDNA and protein levels. Sequence analysis suggests a maize origin for both clones and negligible nucleotide changes linked to PCR. This library is the first described for early plant embryos and represents a breakthrough to isolate genes involved in embryo differentiation.


Subject(s)
Calmodulin/genetics , Gene Library , Genes, Plant/genetics , Zea mays/embryology , Zea mays/genetics , Amino Acid Sequence , Calmodulin/biosynthesis , DNA, Complementary/genetics , Molecular Sequence Data , Plant Proteins/genetics , Polymerase Chain Reaction , Sequence Homology, Amino Acid , Species Specificity
11.
Plant Cell Rep ; 14(12): 743-7, 1995 Oct.
Article in English | MEDLINE | ID: mdl-24186704

ABSTRACT

Fertilized embryo sacs of Zea mays were isolated and cultured In vitro. Each explant contained one zygote and 2-4 endosperm nuclei which formed, respectively, embryo and cellular endosperm during the culture. In our double-layer/two-phase culture system, NBM medium (Mòl et al. 1993) supplemented with 0.1-1.0 mg·l(-1) zeatin and 12 % sucrose showed the best results. On this medium, embryos were isolated from 37-54 % of two-week-old explants. They were similar to maize embryos developing in vivo. We have shown that development of stage-2 embryos (according to Abbe and Stein 1954) with two leaf primordia and normally differentiated provascular tissue is possible from the maize zygote in an in vitro culture system. Some embryos with enlarged and deformed scutellum or whole apical parts were also found. Up to 62 % of the embryos germinating on a simple medium regenerated into mature and fertile plants; i.e. 23 % of explants yielded plants. This unproved culture method results in better embryo differentiation and 14-fold increase of regeneration frequency than previous protocol.

12.
Brain Lang ; 46(2): 329-49, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8137148

ABSTRACT

Twenty-three early-stage dementia of the Alzheimer type (DAT) patients and twenty-three control subjects were tested on a sentence-picture matching test containing nine different sentence types representing different levels of syntactic complexity. Subjects chose between drawings depicting a target sentence and a syntactic foil. Results indicated that DAT patients differed from control subjects on four of the nine sentence types. Performance of the patients was not poorer for sentences that were syntactically more complex, but was poorer for sentences that had two propositions as compared to one. Results are discussed in terms of a post-interpretative processing impairment in sentence comprehension in DAT.


Subject(s)
Alzheimer Disease/diagnosis , Language Disorders/diagnosis , Aged , Alzheimer Disease/complications , Cognition Disorders/diagnosis , Cognition Disorders/etiology , Female , Humans , Language Disorders/etiology , Language Tests , Male , Middle Aged , Semantics , Wechsler Scales
13.
Zygote ; 2(1): 29-35, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7881913

ABSTRACT

Artificial fertilisation was attempted in maize by microinjecting sperm nuclei into the egg cell or central cell of isolated embryo sacs. A protocol for isolation of nuclei from pollen grains was developed and a pure fraction of sperm nuclei was obtained after centrifugation on a Percoll gradient. The in vitro transcriptional activity of the nuclei was tested by incorporation of radioactive UTP into RNA. The level of labelled nucleotide incorporation increased and reached a maximum after between 30 and 40 min in the incubation medium. The embryo sacs were enzymatically isolated and their viability determined by observation of cytoplasmic streaming in the female cells. The embryo sacs were immobilised by embedding in low-melting-point agarose and a single male nucleus was injected with a bevelled microcapillary. The presence of the injected nucleus in the egg or central cell was demonstrated using a cytological approach. This paper presents an alternative method for studying the intimate processes of fertilisation in plants.


Subject(s)
Fertilization , Nuclear Transfer Techniques , Seeds , Zea mays/physiology , Microinjections , Transcription, Genetic , Zea mays/genetics
14.
Q J Exp Psychol A ; 45(2): 177-92, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1410554

ABSTRACT

Several previous studies have shown that memory span is greater for short words than for long words. This effect is claimed to occur even when the short and long words are matched for the number of syllables and phonemes and so to provide evidence for subvocal articulation as being one mechanism that underlies memory span (Baddeley, Thomson, & Buchanan, 1975). The three experiments reported in this paper further investigate the articulatory determinants of word length effects on span tasks. Experiment 1 replicated Baddeley et al.'s finding of an effect of word length on auditory and visual span when the stimuli consist of words that differ in terms of the number of syllables. Experiments 2 and 3 showed that the effects of word length are eliminated when the words in the span task are matched for the number of syllables and phonemes but differ with respect to the duration and/or complexity of their articulatory gestures. These results indicate that it is the phonological structure of a word and not features of its actual articulation that determines the magnitude of the word length effect in span tasks.


Subject(s)
Attention , Mental Recall , Phonetics , Verbal Learning , Aged , Female , Humans , Male , Memory, Short-Term , Middle Aged , Reading , Speech Perception
15.
Plant Physiol ; 85(4): 876-8, 1987 Dec.
Article in English | MEDLINE | ID: mdl-16665823

ABSTRACT

Sperm cells were isolated from corn (Zea mays L.) tricellular pollen grains. They were released using a light osmotic chock, and separated from pollen contaminants (especially starch grains) by a Percoll gradient centrifugation. Isolated sperm cells (3 x 10(6) per milliliter) show a high viability score (90%) as demonstrated with the fluorochromatic reaction. They appeared as spherical cells which lack cell wall and plastids, and can be considered as haploid protoplasts.

16.
Allerg Immunol (Paris) ; 19(6): 235-7, 1987 Jun.
Article in French | MEDLINE | ID: mdl-3331269

ABSTRACT

In flowering plants, the recognition reactions occur between male and female partners at the stigma level or along the style and in the embryo sac between the gametes. The study of these biological events implies to check the viability of the two partners. Interacting molecules are glycoproteins. A cDNA coding for the stigma protein molecules has recently been cloned. The specific pollen molecules have been also characterized. They are glycoproteins which are localized at the periphery of the grain and rapidly diffuse. These recognitive molecules present some analogies with pollen allergens.


Subject(s)
Plant Proteins/physiology , Pollen , Sex Characteristics , Female , Male , Pollen/analysis , Reproduction
17.
Plant Physiol ; 83(3): 464-6, 1987 Mar.
Article in English | MEDLINE | ID: mdl-16665270

ABSTRACT

A technical procedure is described to follow the in vitro release of the ;male germ unit' and the sperm cells from three tricellular pollen species (Brassica, Zea, and Triticum). The condition of the sperm cell was controlled using light microscopy. In addition, for the first time, the sperm cells viability has been checked by the fluorochromatic reaction test. These preliminary results indicate that this procedure appears to be a prerequisite for the successful preparation of purified viable sperm cells.

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