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Erik Oudman Tanja C.W. Nijboer Albert Postma Jan W. Wijnia Sandra Kerklaan Karen Lindsen 《Neuropsychological rehabilitation》2013,23(6):888-913
Patients with Korsakoff's syndrome show devastating amnesia and executive deficits. Consequently, the ability to perform instrumental activities such as making coffee is frequently diminished. It is currently unknown whether patients with Korsakoff's syndrome are able to (re)learn instrumental activities. A good candidate for an effective teaching technique in Korsakoff's syndrome is errorless learning as it is based on intact implicit memory functioning. Therefore, the aim of the current study was two-fold: to investigate whether patients with Korsakoff's syndrome are able to (re)learn instrumental activities, and to compare the effectiveness of errorless learning with trial and error learning in the acquisition and maintenance of an instrumental activity, namely using a washing machine to do the laundry. Whereas initial learning performance in the errorless learning condition was superior, both intervention techniques resulted in similar improvement over eight learning sessions. Moreover, performance in a different spatial layout showed a comparable improvement. Notably, in follow-up sessions starting after four weeks without practice, performance was still elevated in the errorless learning condition, but not in the trial and error condition. The current study demonstrates that (re)learning and maintenance of an instrumental activity is possible in patients with Korsakoff's syndrome. 相似文献
64.
Boelens MC van den Berg A Vogelzang I Wesseling J Postma DS Timens W Groen HJ 《Journal of clinical pathology》2007,60(6):608-614
BACKGROUND: Changes in epithelial cell interactions have been implicated in carcinogenesis, tumour invasion and metastasis. AIM: To screen for altered expression of epithelial adhesion genes in lung cancer development. METHODS: Gene expression profiles were assessed with cDNA expression arrays in eight non-small cell lung cancer (NSCLC) and eight normal bronchi obtained from the same patient. Immunohistochemistry (IHC) and RNA in situ hybridisation (ISH) were used to confirm the most prominently expressed adhesion molecules and to investigate their distribution at protein and mRNA levels. RESULTS: 43 differentially expressed cancer-related genes were identified in adenocarcinoma, squamous cell carcinoma (SCC) and normal bronchus. Five of these genes are related to epithelial adhesion-that is, integrin alpha3 (ITGA3), integrin beta4 (ITGB4), desmoplakin I and II (DSP), plakoglobin, and desmocollin 3 (DSC3). ITGA3 and ITGB4, showing predominantly cell-matrix staining, were up regulated in adenocarcinoma and SCC, respectively. ITGB4 also showed strong staining in SCC with IHC and ISH. Components of the desmosome adhesion complex DSP, plakoglobin and DSC3 were strongly up regulated in SCC and showed a distinct cell-cell staining pattern. DSP and plakoglobin were predominantly present at central, more differentiated tumour cells, whereas DSC3 showed a stronger staining in the peripheral basal cells of SCC tumour areas. CONCLUSIONS: Lack of cellular adhesion may have an important role in the metastatic potency of a primary tumour. A possible association of strong presence and normal-distributed desmosomal molecules in SCC with the less frequent and late pattern of metastasis in SCC as compared with adenocarcinoma is suggested. 相似文献
65.
Mahmoud Hashim Boris M. Pfeiffer Robert Bartsch Maarten Postma Bart Heeg 《Value in health》2018,21(1):9-17
Background
In previous studies, correlation between overall survival (OS) and surrogate endpoints like objective response rate (ORR) or progression-free survival (PFS) in advanced non-small cell lung cancer (NSCLC) was poor. This can be biased by crossover and postprogression treatments.Objectives
To evaluate the relationship between these two surrogate endpoints and OS in advanced NSCLC studies that did not allow for crossover or reported balanced post-progression treatments.Methods
A systematic review in patients with advanced NSCLC receiving second- and further-line therapy was performed. The relationship between the absolute difference in ORR or median PFS (mPFS) and the absolute difference in median OS (mOS) was assessed using the correlation coefficient (R) and weighted regression models. The analysis was repeated in predefined data cuts based on crossover and balance of postprogression treatments. When the upper limit of R’s 95% confidence interval (CI) was more than 0.7, the surrogate threshold effect (STE) was estimated.Results
In total, 146 randomized clinical trials (43,061 patients) were included. The mean ORR, mPFS, and mOS were 12.2% ± 11.2%, 3.2 ± 1.3 months, and 9.6 ± 4.1 months, respectively. The correlation coefficients of ORR and mPFS were 0.181 (95% CI 0.016–0.337) and 0.254 (95% CI 0.074–0.418), respectively, with mOS. Nevertheless, in trials that did not allow crossover and reported balanced postprogression treatments, the correlation coefficients of ORR and mPFS were 0.528 (95% CI 0.081–0.798) and 0.778 (95% CI 0.475–0.916), respectively, with mOS. On the basis of STE estimation, in trials showing significant treatment effect size of 41.0% or more ORR or 4.15 or more mPFS months, OS benefit can be expected with sufficient certainty.Conclusions
Crossover and postprogression treatments may bias the relationship between surrogate endpoints and OS. Presented STE calculation can be used to interpret treatment effect on either ORR or PFS when used as primary endpoints. 相似文献66.
We describe a case of 64-year-old female patient with ventricular tachycardia intractable to medical treatment and acute heart failure following myocardial infarction. Emergency surgical ventricular reconstruction and subendocardial resection was undertaken. We discuss the option of surgical intervention in this difficult and unusual clinical scenario. 相似文献
67.
Dissimilarity in methacholine and adenosine 5'-monophosphate responsiveness 3 and 24 h after allergen challenge 总被引:3,自引:0,他引:3
R Aalbers H F Kauffman G H Ko?ter D S Postma K De Vries J G De Monchy 《The American review of respiratory disease》1991,144(2):352-357
Bronchial hyperresponsiveness (BHR) to methacholine and adenosine 5'-monophosphate (AMP) was studied in 15 allergic asthmatic patients before and 3 and 24 h after allergen challenge with house dust mite (HDM). Subjects attended the clinic on 3 consecutive days. On the first day a control solution was inhaled, and methacholine or AMP challenge was performed 3 h later. The next day HDM was inhaled, and 3 and 24 h later methacholine or AMP challenge was performed again. There were no significant difference in FEV1 baseline value between any of the study days. PD20 HDM, percentage decrease in FEV1, and AUC for both the EAR and LAR were not significantly different in the methacholine and AMP studies. After HDM challenge, PC20 methacholine decreased significantly from a geometric mean (+/- SEM) starting value of 1.39 +/- 0.63 mg/ml to 0.30 +/- 0.78 mg/ml (p less than 0.001) at 3 h and to 0.22 +/- 0.75 mg/ml (p less than 0.001) at 24 h. The magnitude of the decrease in PC20 methacholine at 3 h correlated with the severity of the late asthmatic reaction (LAR) as measured by the percentage fall in FEV1 and area under the curve (AUC) (r = -0.60 and r = 0.55; p less than 0.05). A significant decrease was observed in the PC20 AMP at 3 h, from a geometric mean value of 12.2 +/- 0.96 mg/ml after challenge with the control solution to 4.47 +/- 0.99 mg/ml (p less than 0.05) after HDM challenge.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
68.
Differential coupling of CC chemokine receptors to multiple heterotrimeric G proteins in human interleukin-2-activated natural killer cells 总被引:2,自引:1,他引:2
Using two different approaches, we have investigated the types of G proteins coupled to CC chemokine receptors. First, permeabilization of interleukin-2-activated natural killer (IANK) cells with streptolysin-O and introduction of anti-G protein antibodies inside these cells resulted in the following. (1) Anti-G(s), anti-G(o), and anti-G(z) inhibited the migration of IANK cells in response to macrophage- inflammatory protein-1 alpha (MIP-1 alpha), monocyte chemoattractant protein-1 (MCP-1), or regulated on activation normal T cell expressed and secreted (RANTES). (2) Anti-Gi inhibited their migration in response to MCP-1 or RANTES but not in response to MIP-1 alpha. Second, incubation of IANK cell membranes with anti-G protein antibodies before incubating with (gamma-35S) GTP or (gamma-32P) GTP, resulted in the following. (1) Anti-G(s), anti-G(o), or anti-G(z) inhibited GTP binding and GTPase activity in the presence of MIP-1 alpha, or RANTES. (2) Anti- G(i) inhibited GTP binding and GTPase activity in the presence of MCP-1 or RANTES but not in the presence of MIP-1 alpha. The inhibitory effect of anti-G protein antibodies was reversed upon incubating these antibodies with their respective synthetic peptides before addition to IANK cell membranes. These results suggest that MCP-1 and RANTES receptors are promiscuously coupled to multiple G proteins in IANK cell membranes and that this coupling is different from MIP-1 alpha receptors, which seem to be coupled to G(s), G(o), and G(z) but not to G(i). 相似文献
69.
Crist WM; Shuster JJ; Falletta J; Pullen DJ; Berard CW; Vietti TJ; Alvarado CS; Roper MA; Prasthofer E; Grossi CE 《Blood》1988,72(6):1891-1897
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment. 相似文献
70.
Identification of a second transforming gene, rasn, in a human multiple myeloma line with a rearranged c-myc allele 总被引:1,自引:0,他引:1
Multiple myeloma is a disease characterized by a long, slowly progressive phase and a final, more aggressive one. Little is known about the mechanism of transformation of myeloma cells, although the clinical characteristics of the disease suggest a multi-step process. Recently, a myeloma cell line, NCI-H929, was isolated from a patient with aggressive preterminal disease and found to have a rearranged myc allele. This myeloma cell line has been further characterized in a focus formation assay to determine whether its unusual growth characteristics were associated with a second activated transforming gene. We now report that the NCI-H929 myeloma cell line has an activated rasn allele in addition to a rearranged myc allele. This is the first identification of an activated transforming gene in a multiple myeloma cell line; furthermore, the characterization of two independently activated oncogenes in this B cell malignancy has implications for both the pathogenesis and evolution of the disease. 相似文献