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Objective The aim of the present study is to provide further insight into semantic processing in Working Memory (WM) in two amnesic patients with extensive medial temporal lobe (MTL) by adopting a short length word-lists recall task. Background It is still unclear whether the medial temporal lobe structures and especially the hippocampus is recruited in semantic processing in the context of WM. Materials & methods Two severely amnesic patients with extensive MTL damage due to herpes simplex encephalitis (HSE) and a control group ( n = 36) underwent an experimental task involving the immediate free recall of 9 word-lists in three different conditions: 1. semantically related words clustered according to semantic category (SRC), 2. semantically related words non-clustered (SRnC), 3. semantically unrelated words (SU). Additionally, standard cognitive measures were administered [Digit Span Forward & Backward, Greek Verbal Learning Test (GVRT), Verbal Fluency Test (VFT), Logical Memory I & II (LM-I & LM-II) of Wechsler Memory Scale (WMS)]. Results Both patients obtained normal performance in WM tests (Digit Span Forward & Backward), but were impaired in GVRT, VFT, LM-I and LM-II. With regard to the word-list task, the number of words recalled by both patients’ did not differ from controls. However, semantic facilitation effects were not recorded in patients’ performance for the SRC and SRnC conditions (SRC = SRnR = SU), unlike controls (SRC > SRnC > SU). Conclusions Our results suggest that the effects of semantic facilitation in short length word-lists recall are diminished to a certain degree in HSE patients that suffer from MTL damage.

Research that focuses on the lived meaning of specific phenomena with pedagogical significance in physical education is very limited. Moreover, the relevant literature concerns studies that explore...

Background Cognitive event-related potentials (ERPs) have been previously correlated with T2 lesion load (Τ2LL) in patients with multiple sclerosis (MS). It is currently unknown, however, whether ERPs also correlate with brain atrophy or the presence of T1 hypointense lesions (“black holes”) which reflect tissue destruction and axonal loss. The primary aim of the current study is to explore the effect of neuroradiological parameters such as brain atrophy, T1 and T2 lesion load on auditory ERPs in MS patients. In addition, we correlated cognitive impairment with neurophysiological (ERP) and neuroradiological (MRI) variables and investigated whether a combination of ERP and MRI parameters is capable of distinguishing patients suffering from secondary progressive (SP), primary progressive (PP) and relapsing-remitting (RR) MS. Materials and methods The study sample consisted of fifty nine MS patients (mean age±SD: 37.82±1.38 years; average disease duration: 6.76±5.3 years) and twenty six age-matched controls (mean age±SD: 41.42±15.39 years). The patients’ EDSS and NRS scores were 3.77±2.14 (range: 1–7.5) and 75.88±11.99 (range: 42–94) respectively. ERPs were recorded using the auditory “odd-ball” paradigm. T1 and T2 lesions were automatically segmented using an edge-finding tool and total lesion volumes were calculated. MRI measures of brain atrophy included third ventricle width (THIRDVW) and the ratio of mid-sagittal corpus callosum area to the mid-sagittal intracranial skull surface area (CC/MISS). Statistical analysis was performed using multiple regression, principal component (PCA) and discriminant analysis. Results T1 lesion load emerged as the most significant predictor of P300 and N200 latency. The rest of the endogenous ERPs parameters (P300 amplitude, N200 amplitude) were not significantly correlated with the MRI variables. PCA of pooled neuroradiological and neurophysiological markers suggested that four components accounted for 64.6% of the total variability. Discriminant analysis based on ERP & MRI markers classified correctly 79.63% of patients in RR, PP and SP subgroups. Conclusion T1 lesion load is the most significant MRI correlate of auditory ERPs in MS patients. Importantly, ERPs in combination with MRI variables can be usefully employed for distinguishing patients with different subtypes of MS.

Canavan's disease (CD) is a hereditary leukodystrophy caused by mutations in the aspartoacylase gene (ASPA), leading to spongiform degeneration of the white matter and severe impairment of psychomotor development. We present the cases of two non-Jewish sisters with CD that have a milder and protracted clinical course compared to typical CD. MRI imaging revealed bilateral high-signal-intensity areas in the thalami and the internal capsule and MR spectroscopy showed typical findings for CD (a marked increase in N-acetylaspartate (NAA) levels). FA values of the right and left corticospinal tracts at the level of the posterior limb of the internal capsule, and the centrum semiovale were found to be significantly reduced compared to healthy controls. From a neurophysiological point of view, the peripheral motor system was normal. In contrast, cortical stimulation at maximal intensity failed to elicit facilitated or resting MEPs and silent periods (SPs) in upper and lower limbs, providing evidence for significant upper motor pathway dysfunction.

Monitoring of BCR-ABL transcripts has become established practice in the management of chronic myeloid leukemia. However, nucleic acid amplification techniques are prone to variations which limit the reliability of real-time quantitative PCR (RQ-PCR) for clinical decision making, highlighting the need for standardization of assays and reporting of minimal residual disease (MRD) data. We evaluated a lyophilized preparation of a leukemic cell line (K562) as a potential quality control reagent. This was found to be relatively stable, yielding comparable respective levels of ABL, GUS and BCR-ABL transcripts as determined by RQ-PCR before and after accelerated degradation experiments as well as following 5 years storage at -20 degrees C. Vials of freeze-dried cells were sent at ambient temperature to 22 laboratories on four continents, with RQ-PCR analyses detecting BCR-ABL transcripts at levels comparable to those observed in primary patient samples. Our results suggest that freeze-dried cells can be used as quality control reagents with a range of analytical instrumentations and could enable the development of urgently needed international standards simulating clinically relevant levels of MRD.