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1.
Macoir J 《Neuropsychologia》2009,47(2):518-535
The concreteness effect, which refers to the typically superior performance for concrete concepts compared to abstract ones, is a robust phenomenon that has been observed in normal and brain-damaged subjects in a number of cognitive domains. Reversal of this effect was also reported in a few neuropsychological studies, mainly in patients with semantic dementia (SD). In this article, we report the first longitudinal single-case study of a patient with SD, SC, who performed better for abstract than concrete concepts in various comprehension and production tasks. For concrete concepts, SC showed no category-specific deficit but was impaired in tasks exploring access to stored structural knowledge and semantic perceptual attributes. With the course of the disease, the semantic system progressively declined and the reversal of the concreteness effect, as well as the dissociation between perceptual and non-perceptual knowledge, vanished. We discuss the results and their implications for theoretical propositions of concreteness effect as well as theoretical models of semantic memory. We suggest that the reversal of concreteness in SC is a direct result of the degradation of visual feature knowledge, sustained by anatomical structures affected early in SD. With the time course of the disease, the atrophy extends to adjacent regions and the dissociation between abstract and concrete concepts was no longer observed.  相似文献   

2.
In acute myocardial infarction, the perfusion status frequently fluctuates with rapid occurrences of coronary occlusion followed by myocardial ischemia. In patients with unstable angina, most episodes of ischemia are not accompanied by chest pain. In these patients it is important to be able to monitor the results of medical treatment non-invasively to establish the need for further intervention. It is not feasible to perform coronary angiography in all patients with acute myocardial infarction to evaluate patency of the infarct-related artery. Furthermore, even in a patent artery, no reflow may be present in the myocardial tissue. Angiography is therefore not the perfect golden standard to compare noninvasive ischemia monitoring with. Prognosis seems to be a better standard for comparison. This review indicates that vectorcardiography monitoring may identify myocardial reperfusion at an early stage and gives valuable prognostic information both in patients with unstable angina and acute myocardial infarction with low interobserver variability.  相似文献   

3.
Whipple disease is a granulomatous infectious disease caused by Tropheryma whipplei. The bacteria accumulate within macrophages, preferentially in the intestinal mucosa. Disease manifestation seems to be linked to immunological abnormalities of macrophages. We describe a patient with cerebral Whipple disease who presented with changes in mental status, confusion, inverse sleep-wake cycle, bilateral ptosis and vertical gaze palsy. Endoscopic biopsy sampling revealed Whipple disease in the gastric antrum but not in the duodenum. Whole blood stimulation displayed reactivity to T. whipplei that was at the lower end of healthy controls while reactivity of duodenal lymphocytes was not diminished. We propose that in cases of neurological symptoms suspicious of Whipple disease with normal duodenal and jenunal findings, biopsy sampling should be extended to the gastric mucosa. The robust reactivity of duodenal lymphocytes may have prevented our patient from developing small bowel disease, whereas the impaired reactivity in peripheral blood lymphocytes might yet explain the bacterial spreading to the central nervous system leading to the rare case of predominant neurological symptoms without relevant systemic involvement.  相似文献   

4.
5.
The objective of this study was to conduct a randomized controlled trial to examine the effects of a way-finding intervention on residents' ability to find their way in a new environment. The effect of the intervention on the residents' spatial orientation and agitation were also examined. The study was conducted on four nursing home units in a geriatric center and the final sample consisted of 32 residents with Alzheimer's disease (17 in the treatment group and 15 in the control group). The intervention consisted of the use of a location map and a behavioral training technique, which was provided to residents over the course of a month. Repeated measures analysis of variance and McNemar tests were used to compare the groups in regard to changes in the outcomes over time. Results indicated that the residents' in the treatment group demonstrated an increased ability to find their way to the dining room one week after the intervention. The intervention effect was not sustained three months later.  相似文献   

6.
Epidemiological studies indicate that the intake of Mediterranean-style diet is inversely associated with risk of stroke, cardiovascular diseases, and cancer. Spirulina is widely used nutritional supplement rich in proteins and antioxidants. Evidence demonstrates that the impaired energy metabolism and the excessive generation of reactive oxygen radicals contribute to the brain injury associated with cerebral ischemia. In the present study, the protective effect of Spirulina was investigated in transient middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia–reperfusion injury in rats. Male albino rats were divided into six groups: control, sham-operated group, ischemic control group, and Spirulina-pretreated groups (45, 90 and 180 mg/kg/p.o.). Spirulina was administered once a day, for 7 days. The rats were subjected to a 2-h right MCAO via the intraluminal filament technique and 22 h of reperfusion. Pretreatment with Spirulina significantly reduced the histological changes and neurological deficits. Spirulina at a dose of 180 mg/kg significantly reversed the elevated brain malondialdehyde (MDA) content and restored the decreased activities of brain superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) indicating that Spirulina has the protective potential against cerebral ischemia injury and its protective effects may be due to its antioxidant property.  相似文献   

7.
8.
BACKGROUND: Administration of novel, versus classic, antipsychotic agents to patients suffering from psychosis is associated both with moderately better scores on cognitive tests, and with fewer extrapyramidal symptoms (EPS). Because improved motor functioning may enable better performance on some components of cognitive test batteries, and because the advantages of the novel antipsychotics on cognitive performance are not very large, it is sometimes difficult to discern if improvement in a given cognitive task is due to a direct effect of the novel antipsychotic drug, or is secondary to the novel drug's decreased propensity to induce EPS. In an attempt to distinguish between these two possibilities, the present study examined the ability of patients suffering from schizophrenia receiving classic, versus novel antipsychotics, to perform a computerized visuo-motor test (VMT). VMT assesses planning capabilities, attention and executive functions known to be impaired in schizophrenia, which are suggested to be affected by novel antipsychotics. METHODS: Seventy-six patients suffering from schizophrenia or schizophreniform disorder, receiving haloperidol (23 patients, mean dose 10.01+/-6.1mg/day), olanzapine (26 patients, mean dose 10.56 +/- 4.9 mg/day) or risperidone (27 patients, mean dose 4.35 +/- 1.7 mg/day) were assessed for EPS using the parkinsonian subscale of the Extrapyramidal Symptom Rating Subscale (ESRS), and with the VMT. RESULTS: Cognitive functioning as measured by the VMT was better for patients receiving risperidone or olanzapine, compared with those receiving haloperidol (F=6.636, df=2,67, P=0. 002), while the patients receiving haloperidol or risperidone suffered from more severe EPS compared with the patients receiving olanzapine (F=3.996, df=2,71, P=0.023). DISCUSSION: Although the patients receiving risperidone suffered from EPS similar in severity to the EPS of the patients receiving haloperidol, their performance on a task involving visuo-motor and attentional skills was similar to that of the patients receiving olanzapine. This finding implies that there is a dissociation between the antipsychotic drug's ability to affect cognitive functioning, and EPS. This dissociation indirectly suggests that the advantages offered by novel antipsychotics on cognitive performance are a direct effect, rather than being entirely mediated by improved movement abilities.  相似文献   

9.
BACKGROUND: Antipsychotic treatment in schizophrenia is frequently associated with extrapyramidal side effects. Objective behavioural measures to evaluate the severity of extrapyramidal side effects in the clinical setting do not exist. OBJECTIVES: This study was designed to investigate grasping movements in five drug naive and 13 medicated subjects with schizophrenia and to compare their performance with that of 18 healthy control subjects. Deficits of grip force performance were correlated with clinical scores of both parkinson-like motor disability and psychiatric symptom severity METHODS: Participants performed vertical arm movements with a handheld instrumented object and caught a weight that was dropped into a handheld cup either expectedly from the opposite hand or unexpectedly from the experimenter's hand. The scaling of grip force and the temporospatial coupling between grip and load force profiles was analysed. The psychiatric symptom severity was assessed by the positive and negative symptom score of schizophrenia and the brief psychiatric rating scale. Extrapyramidal symptoms were assessed by the unified Parkinson's disease rating scale. RESULTS: Drug naive subjects with schizophrenia performed similar to healthy controls. In contrast, medicated subjects with schizophrenia exhibited excessive grip force scaling and impaired coupling between grip and load force profiles. These performance deficits were strongly correlated with the severity of both extrapyramidal side effects related to antipsychotic therapy and negative symptoms related to the underlying pathology. CONCLUSIONS: These data provide preliminary evidence that deficits of sensorimotor performance in schizophrenia are, at least in part, related to the side effects of antipsychotic treatment. The investigation of grasping movements may provide a sensitive measure to objectively evaluate extrapyramidal side effects related to antipsychotic therapy.  相似文献   

10.
《中国神经再生研究》2016,(7):1102-1107
Angiotensin Ⅱ type 2 receptor(AT2R) activation has been shown to protect against stroke,but its precise mechanism remains poorly understood.We investigated whether the protective effect of AT2 R against ischemia/reperfusion injury is mediated by the suppression of immune and inflammatory responses.Rat models of middle cerebral artery occlusion were intraperitoneally injected with physiological saline,the AT2 R agonist CGP42112(1 mg/kg per day) or antagonist PD123319(1 mg/kg per day).In the CGP42112 group,AT2 R expression increased,the infarct area decreased,interleukin-1β and tumor necrosis factor-α expression decreased,and interleukin-10 expression increased compared with the saline group.Antagonisin AT2 R using PD123319 produced the opposite effects.These results indicate that AT2 R activation suppresses immune and inflammatory responses,and protects against cerebral ischemia/reperfusion injury.  相似文献   

11.
Space perception was investigated in two groups of participants with severe visual deficiencies performing a tactile bisection task: the participants in the first group (Archers) regularly practised a high-precision sport, whereas those in the second group (Non-Archers) had never practised this activity. Experiments were carried out to determine whether practising this sport might affect the pseudoneglect (resulting in a deviation to the left of the perceived midpoint with respect to the actual physical midpoint) occurring in sighted persons (Bowers & Heilman, 1980) as well as in completely blind children (Sampaio, Gouarir, & Mvondo Mvondo, 1995). No particular deviation was observed in the group of Non-Archers, whereas pseudoneglect was present in the Archers' group. A significant hand effect (left/right), and a significant effect of starting point of tactile exploration were observed across groups. This confirms the existence of a relationship between hemisphere-hands and hemisphere-hemispace mechanisms. The results obtained here show that practising archery affects pseudoneglect.  相似文献   

12.
OBJECTIVE: The current study examined the validity of using comorbid obsessive-compulsive personality disorder (OCPD) to identify a subtype of individuals with obsessive-compulsive disorder (OCD). METHOD: Data for the current study were drawn from an ongoing, longitudinal study of the course of OCD and include intake assessments for 238 subjects with primary and current DSM-IV OCD who were treatment seeking. RESULTS: More than one fourth of the subjects (N=65, 27%) met criteria for comorbid OCPD. As compared to OCD-OCPD subjects, the OCD+OCPD subjects had a significantly younger age at onset of first OC symptoms (p=0.013), and a higher rate of symmetry and hoarding obsessions, and cleaning, ordering, repeating, and hoarding compulsions (all p's<0.01). Individuals with OCD+OCPD had higher rates of comorbid anxiety disorders (p=0.007) and avoidant personality disorder (p=0.006). The OCD+OCPD subjects also had significantly lower ratings of global functioning (p=0.001) and more impaired social functioning (p=0.004), despite a lack of significant differences on overall severity of OCD symptoms. CONCLUSIONS: Our findings indicate that individuals with both OCD and OCPD have distinct clinical characteristics in terms of age at onset of initial OC symptoms, the types of obsessions and compulsions they experience, and psychiatric comorbidity. Our findings, coupled with data from family studies showing a higher than expected frequency of OCPD in first degree relatives of OCD probands, suggest that OCD associated with OCPD may represent a specific subtype of OCD. Additional research is warranted to further establish the validity of this subtype.  相似文献   

13.
14.
Lithium, which is approved for treating patients with bipolar disorder, is reported to inhibit 3′(2′)-phosphoadenosine-5′-phosphate (PAP) phosphatase activity. In yeast, deletion of PAP phosphatase results in elevated PAP levels and in inhibition of sulfation and of growth. The effect of lithium on PAP phosphatase is remarkable for the low Ki (~0.2 mM), suggesting that this system would be almost completely shut down in vivo with therapeutic levels of 1 mM lithium, thereby elevating PAP levels. To test the hypothesis that lithium inhibition of PAP phosphatase is pharmacologically relevant to bipolar disorder, we fed rats LiCl for 6 weeks, and assayed brain PAP levels after subjecting the brain to high-energy microwaving. We also measured PAP phosphatase mRNA and protein levels in frozen brain tissue of lithium-treated mice. Brain adenosine phosphates were extracted by trichloroacetic acid and assayed by HPLC with a gradient system of two phases. PAP phosphatase mRNA was measured by RT-PCR, and PAP phosphatase protein was measured by Western blotting. Brain PAP levels were below detection limit of 2 nmol/g wet weight, even following lithium treatment. Lithium treatment also did not significantly change brain PAP phosphatase mRNA or protein levels. These results question the relevance of PAP phosphatase to the therapeutic mechanism of lithium. A statistically significant 25% reduced brain ADP/ATP ratio was found following lithium treatment in line with lithium’s suggested neuroprotective effects.  相似文献   

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16.
Gamma-hydroxybutyrate (GHB) has re-emerged as a major treatment for narcolepsy. As dopaminergic transmission is clearly involved in the pathophysiology of restless legs syndrome (RLS), and GHB reduces dopamine release, one may hypothesize that RLS may occur in narcolepsy in the presence of GHB. We report a case of narcolepsy with a severe occurrence of typical RLS with GHB, symptoms never previously experienced by the subject and reversible after withdrawal.  相似文献   

17.
The concreteness effect, which refers to the typically superior performance for concrete concepts compared to abstract ones, is a robust phenomenon that has been observed in normal and brain-damaged subjects in a number of cognitive domains. Reversal of this effect was also reported in a few neuropsychological studies, mainly in patients with semantic dementia (SD). In this article, we report the first longitudinal single-case study of a patient with SD, SC, who performed better for abstract than concrete concepts in various comprehension and production tasks. For concrete concepts, SC showed no category-specific deficit but was impaired in tasks exploring access to stored structural knowledge and semantic perceptual attributes. With the course of the disease, the semantic system progressively declined and the reversal of the concreteness effect, as well as the dissociation between perceptual and non-perceptual knowledge, vanished. We discuss the results and their implications for theoretical propositions of concreteness effect as well as theoretical models of semantic memory. We suggest that the reversal of concreteness in SC is a direct result of the degradation of visual feature knowledge, sustained by anatomical structures affected early in SD. With the time course of the disease, the atrophy extends to adjacent regions and the dissociation between abstract and concrete concepts was no longer observed.  相似文献   

18.

Background

The aims of this study are to describe the methodological challenges in recruiting a follow-up sample of children referred to an interdisciplinary hospital child protection team (CPT) and to compare participating versus non-participating groups on several demographic variables and maltreatment characteristics.

Methods

Of the 319 in- and outpatients referred to the CPT at University Children's Hospital Zurich from 2005–2006 a sample of 180 children was drawn to contact for a follow-up. The children and their parents were asked to participate in a face-to-face interview at the hospital; in 42 cases the children and parents consented to do so. Alternatively, the parents could take part in a telephone interview (n = 39). Non-participation resulted because no contact or adequate communication in German, French, or English could be established (n = 49) or because the parents or children refused to participate (n = 50).

Results

Participants and non-participants did not differ significantly in mean child age at follow-up, gender, family status, place of residence, certainty and type of maltreatment, and type of perpetrator. However, the child's nationality had a significant impact: Percentages of foreign nationals were higher in the fully participating group (45%; n = 19) and the non-contactable group (53%; n = 26) and significantly lower in the refusal (26%; n = 10) and the telephone interview group (18%; n = 9). Although a high percentage of families had moved in the few years since the CPT intervention (32%; n = 57), the percentage of moves was not significantly higher in non-participants compared to participants.

Conclusions

Further research is needed to support these results in different national backgrounds and to test for biases in variables not included – especially socioeconomic status. This includes gathering more detailed information on non-participants, while respecting ethical boundaries. Overall, the fact that only child's nationality was unevenly distributed between participants and non-participants is encouraging.  相似文献   

19.
In this paper, it is argued that a psychology of loss can help to illuminate one of the central themes of positive psychology: That is, showcasing those human skills that emphasize human strengths and optimal functioning. However, the interface of positive psychology and a psychology of loss also contains a definite paradox. Loss is not an intrinsically positive event that will necessarily build human strength. Yet, the experience of loss can become a profound means for showcasing human strengths and potential. We also caution that a positive psychology, in its quest to focus on the more uplifting qualities of the human experience, must also realize that suffering and loss is inherent to the human condition.  相似文献   

20.
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