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Dementia, even at an early stage, may pose problems and challenge one's quality of life. Having accurate knowledge of what one experiences when living with dementia is important for developing proactive care for individuals with dementia and their families. The aim of our Grounded Theory study was to explore what it means for elderly people to live with early-stage dementia. We interviewed 20 elderly people with probable mild dementia and their family members. Living with dementia was often presented as a positive narrative, one that told of only minor problems and which stressed abilities and contentment with life. Being valued, rather than losing one's cognition or identity was central in their experience. More in-depth analyses of participants' narratives revealed, however, that they were constantly balancing their feelings of value and worthlessness, struggling to remain someone of value. This struggle was prompted by threats posed by dementia and by the persons' interactions with others. Superficially, a positive narrative may be understood as a lack of awareness or as denial due to cognitive loss. Our findings suggest, however, that we should look beyond this superficial view and seek to understand the narrative as an expression of one's attempt to counterbalance devaluation.  相似文献   
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In this study, we examined the role of the hippocampus in relational memory by comparing item recognition performance in amnesic patients with medial temporal lobe (MTL) damage and their matched controls. Specifically, we investigated the contribution of associative memory to item recognition using a cued recognition paradigm. Control subjects studied cue-target pairs once, whereas amnesic patients studied cue-target pairs six times. Following study, subjects made recognition judgments about targets that were presented either alone (no cue), with the originally presented cue (same cue), or with a cue that had been presented with a different target (recombined cue). Controls had higher recognition scores in the same cue than in the recombined cue condition, indicating that they benefited from the associative information provided by the same cue. By contrast, amnesic patients did not. This was true even for a subgroup of patients whose recognition performance in the no cue condition was matched to that of the controls. These data provide further support for the idea that the hippocampus plays a critical role in relational memory, even when associative information need not be retrieved intentionally.  相似文献   
55.
A large number of studies have reported on the validity of autism spectrum disorder (ASD) screening procedures. An overall understanding of these studies’ findings cannot be based solely on the level of internal validity of each, since screening instruments might perform differently according to certain factors in different settings. Europe has led the field with the development of the first screening tool and first prospective screening study of autism. This paper seeks to provide an overview of ASD screening studies and ongoing programmes across Europe, and identify variables that have influenced the outcomes of such studies. Results show that, to date, over 70,000 children have been screened in Europe using 18 different screening procedures. Differences among findings across studies have enabled us to identify ten factors that may influence screening results. Although it is impossible to draw firm conclusions as to which screening procedure is most effective, this analysis might facilitate the choice of a screening method that best fits a specific scenario, and this, in turn, may eventually improve early ASD detection procedures.  相似文献   
56.
Background: Increasingly, computerised communication aids are used by people with severe, chronic aphasia. Although the candidacy for these devices is relatively unknown, it has been hypothesised that cognitive deficits have a negative impact on the functional use of Augmentative and Alternative Communication (AAC). Deficits of executive functioning are assumed to be particularly important, but other functions, such as memory and semantic processing, may also be relevant. In a previous study (van de Sandt‐Koenderman, Wiegers, Wielaert, Duivenvoorden, & Ribbers, in press van de Sandt‐Koenderman, M., Wiegers, J., Wielaert, S. M., Duivenvoorden, H. J. and Ribbers, G. M. in press. A computerised communication aid in severe aphasia: An exploratory study.. Disability and Rehabilitation,  [Google Scholar]) we reported the functional effect of TouchSpeak (TS), a computerised communication aid, in a group of stroke patients with severe aphasia. The successful participants showed different levels of proficiency. Some were able to use the system independently and creatively in many situations, some used it independently for trained situations, and others remained partner dependent in using TS.

Aims: To find factors associated with the functional success of TS in people with severe aphasia, focusing on memory, executive functioning, semantic processing, and communication skills.

Methods & Procedures: The data of 30 patients with severe aphasia were analysed retrospectively. All were trained to use TS in two self‐chosen communicative situations. Four outcome levels were differentiated: no use, dependent use, independent use, and extensive use of TS. Pre‐training assessment included memory, executive functioning, semantic processing, and communication skills. The four outcome groups were compared regarding age, time post onset, gender, and aphasia type. The role of the cognitive variables was analysed with univariate ANCOVAs with contrast analysis, with correction for age, gender, aphasia type, or time post onset in case of significant differences between the groups on these variables.

Outcomes & Results: Seven participants were classified as extensive users of TS, five were independent TS users, and five were partner dependent. In 13 cases there was no functional use of TS. Extensive users were younger than the other outcome groups. Independent of this age effect, there was an effect of semantic processing; the no‐use group scored significantly lower on semantics than all other groups.

Conclusions: Only a minority of patients with severe aphasia may be expected to become independent, flexible users of high‐tech AAC. The finding that functional success was related to semantic processing is clinically important. Prospective studies are needed to support the predictive value of semantic processing for high‐tech AAC use. The importance of intact executive functioning is not supported in this study. The broad concept of “executive functioning” needs to be studied in more detail in relation to aphasia.  相似文献   
57.
Background: Aphasia rehabilitation should comprise a family-centred approach, involving main conversation partners in the rehabilitation process as soon as possible. A standardised approach to conversation partner training (CPT) became available in the Netherlands with the release of Partners of Aphasic clients Conversation Training (PACT). PACT was introduced in clinical practice in a multi-centre implementation study with 34 participating dyads.

Aims: To explore candidacy for CPT by describing the characteristics of dyads where the conversation partner engaged in CPT and to identify which characteristics had the potential to predict benefit of PACT.

Methods and Procedures: A pre-post treatment design was used in a multi-centre study. Pre- and post-CPT measures of psychosocial characteristics (caregiver burden, depression and coping) from the partner and behavioural characteristics (cognitive, linguistic and communicative) from the person with aphasia (PWA) were collected. Partner experience was assessed using four scales from the Intrinsic Motivation Inventory. Pre-post measures were analysed using paired T-tests and Wilcoxon signed ranks tests. Multiple regression analyses were used to assess potential predictors of training outcomes.

Outcomes and Results: Partners of people with moderate to severe aphasia engaged in PACT when it was first introduced in clinical practice (N = 34 dyads). Mean time post-onset was 11.5 months. Partners enjoyed the practical training in which they actively engaged through experiential learning methods. Partner scores increased significantly over the intervention time on task-oriented and avoidance-oriented coping skills and their symptoms of depression lowered significantly. Caregiver esteem was found to be a positive predictor of feelings of competence and enjoyment with the training. Older partners enjoyed the training less. More effort was given to the training by the partner when the aphasia was more severe.

Conclusions: This study found that partners are willing to engage in CPT once the PWA returned home and the dyads were engaging in more everyday conversations in their home environment. The results underline the importance of partner characteristics, such as motivation, coping style and a positive outlook on caregiving as possible selection criteria for CPT.  相似文献   

58.

Background

In humans, in utero exposure to ionising radiation results in an increased prevalence of neurological aberrations, such as small head size, mental retardation and decreased IQ levels. Yet, the association between early damaging events and long-term neuronal anomalies remains largely elusive.

Methods

Mice were exposed to different X-ray doses, ranging between 0.0 and 1.0 Gy, at embryonic days (E) 10, 11 or 12 and subjected to behavioural tests at 12 weeks of age. Underlying mechanisms of irradiation at E11 were further unravelled using magnetic resonance imaging (MRI) and spectroscopy, diffusion tensor imaging, gene expression profiling, histology and immunohistochemistry.

Results

Irradiation at the onset of neurogenesis elicited behavioural changes in young adult mice, dependent on the timing of exposure. As locomotor behaviour and hippocampal-dependent spatial learning and memory were most particularly affected after irradiation at E11 with 1.0 Gy, this condition was used for further mechanistic analyses, focusing on the cerebral cortex and hippocampus. A classical p53-mediated apoptotic response was found shortly after exposure. Strikingly, in the neocortex, the majority of apoptotic and microglial cells were residing in the outer layer at 24 h after irradiation, suggesting cell death occurrence in differentiating neurons rather than proliferating cells. Furthermore, total brain volume, cortical thickness and ventricle size were decreased in the irradiated embryos. At 40 weeks of age, MRI showed that the ventricles were enlarged whereas N-acetyl aspartate concentrations and functional anisotropy were reduced in the cortex of the irradiated animals, indicating a decrease in neuronal cell number and persistent neuroinflammation. Finally, in the hippocampus, we revealed a reduction in general neurogenic proliferation and in the amount of Sox2-positive precursors after radiation exposure, although only at a juvenile age.

Conclusions

Our findings provide evidence for a radiation-induced disruption of mouse brain development, resulting in behavioural differences. We propose that alterations in cortical morphology and juvenile hippocampal neurogenesis might both contribute to the observed aberrant behaviour. Furthermore, our results challenge the generally assumed view of a higher radiosensitivity in dividing cells. Overall, this study offers new insights into irradiation-dependent effects in the embryonic brain, of relevance for the neurodevelopmental and radiobiological field.

Electronic supplementary material

The online version of this article (doi:10.1186/1866-1955-7-3) contains supplementary material, which is available to authorized users.  相似文献   
59.
PURPOSE: To study possible causes of motility disturbances that may result from orbital decompression surgery in patients with Graves orbitopathy and especially the role of rectus extraocular muscle paths. METHODS: Sixteen patients with Graves orbitopathy were studied before and 3 to 6 months after translid (6 patients) and coronal (10 patients) orbital decompression surgery for disfiguring proptosis. Ocular motility changes were measured by comparing maximum ductions and severity of diplopia, and the positions and the displacements of the anterior rectus muscle paths were objectively measured using cine magnetic resonance imaging (MRI). RESULTS: Averaged preoperative rectus muscle path positions were not different from those in normal subjects. Averaged postoperative muscle path positions were generally the same as preoperative paths. The only significant exceptions were centrifugal (outward from the orbital axis) displacements of the inferior rectus (IR) muscle path after translid surgery, and of the medial rectus (MR) muscle path after coronal surgery. The amount of IR path displacement with translid surgery was directly correlated with range of depression and with severity of vertical diplopia. The amount of MR path displacement with coronal surgery was inversely correlated with range of abduction and directly correlated with severity of horizontal diplopia. CONCLUSIONS: The anterior orbital connective tissue seems to form a "functional skeleton" that is usually (except as noted for IR and MR) capable of keeping the rectus muscle paths aligned after decompression surgery and preserving the normal functions of rectus muscle pulleys. The centrifugal displacement of the IR and MR may increase the elastic component of the muscle force, leading to the specific patterns of motility disturbance that may occur in some patients after translid and coronal surgery. These findings suggest that standard surgical management of Graves orbitopathy should be supplemented.  相似文献   
60.
Background and aims Human VAT-1 (hVAT-1) is a homologue of the synaptic vesicle membrane protein of Torpedo californica. Its coding gene is located near the BRCA1 locus and thus hVAT-1 may be linked to an inherited predisposition to breast and ovary cancer. However, the hVAT-1 protein expression pattern in normal epithelial tissues such as skin, mammary gland and ovary, as well as in tumours of the mammary gland and ovary, has not been studied.Methods To address this issue, an immunohistological analysis of biopsies of normal epidermis and lesional epidermis of bullous pemphigoid and pemphigus vulgaris patients was undertaken.Results hVAT-1-expression was observed in basal keratinocytes of lesional epidermis of bullous pemphigoid patients but not in normal epidermis or in lesional epidermis of pemphigus vulgaris patients. Moreover, hVAT-1 expression in HaCaT cells was found to be calcium-dependent. Normal and malignant mammary and ovary epithelium were found to be hVAT-1-negative.Conclusions Our results indicate that hVAT-1 exerts a specific function in keratinocyte physiology, in particular in calcium-regulated processes, with no evident deregulation in malignancies of the breast and ovary.Abbreviations BRCA1 Breast-related cancer antigen 1 - DMEM Dulbecco's modified Eagle's medium - EDTA Ethylenediamine tetraacetate - ELISA Enzyme-linked immunosorbent assay - FCS Fetal calf serum - GAPDH Glyceraldehyde-3-phosphate dehydrogenase - GST Glutathione-S-transferase - HRP Horseradish peroxidase - hVAT-1 Human VAT-1 - NHEK Normal human epidermal keratinocytes - PBS Phosphate-buffered saline - TBS Tris-buffered saline - VAT-1 Vesicle-amine-transport protein-1  相似文献   
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