A combined therapy for limb apraxia and related anosognosia.

Left hemisphere stroke frequently leads to limb apraxia, a disorder that has been reported to impact independence in daily life and rehabilitation success. Nonetheless, there is a shortcoming in research and availability of applicable trainings. Further, to date, anosognosia for limb apraxia has largely been neglected. Therefore, we developed a Naturalistic Action Therapy that trains object selection and application with an errorless learning approach and which includes supported self-evaluation. The current study presents the results of two stroke patients participating in the training. The procedure entailed two baseline and one post-training sessions including standardized limb apraxia and anosognosia assessments as well as 18 naturalistic action tasks. The training consisted of 15 sessions during which 4-6 of the 18 naturalistic action tasks (e.g., pour water into a glass, make a phone call) were trained. Both patients showed improvement in trained and untrained tasks as well as in standardized apraxia and anosognosia assessments. Training effects appeared strongest for the trained items. The procedure is documented in detail and easy to administer and thus may have the potential to be applied by relatives. The results of this pilot-study are promising and suggest that the approach is suitable for further evaluation.

Programme Dementia Prevention (pdp): A Nationwide Program for Personalized Prevention in Luxembourg.

BACKGROUND: With continuously aging societies, an increase in the number of people with cognitive decline is to be expected. Aside from the development of causative treatments, the successful implementation of prevention strategies is of utmost importance to reduce the high societal burden caused by neurodegenerative diseases leading to dementia among which the most common cause is Alzheimer's disease. OBJECTIVE: The aim of the Luxembourgish "programme dementia prevention (pdp)" is to prevent or at least delay dementia in an at-risk population through personalized multi-domain lifestyle interventions. The current work aims to provide a detailed overview of the methodology and presents initial results regarding the cohort characteristics and the implementation process. METHODS: In the frame of the pdp, an extensive neuropsychological evaluation and risk factor assessment are conducted for each participant. Based on the results, individualized multi-domain lifestyle interventions are suggested. RESULTS: A total number of 450 participants (Mean age = 69.5 years; SD = 10.8) have been screened at different recruitment sites throughout the country, among whom 425 participants (94.4%) met the selection criteria. CONCLUSIONS: We provide evidence supporting the feasibility of implementing a nationwide dementia prevention program and achieving successful recruitment of the target population by establishing a network of different healthcare providers.

Remodeling of the focal adhesion complex by hydrogen-peroxide-induced senescence.

Cellular senescence is a phenotype characterized by cessation of cell division, which can be caused by exhaustive replication or environmental stress. It is involved in age-related pathophysiological conditions and affects both the cellular cytoskeleton and the prime cellular mechanosensors, focal adhesion complexes. While the size of focal adhesions increases during senescence, it is unknown if and how this is accompanied by a remodeling of the internal focal adhesion structure. Our study uses metal-induced energy transfer to study the axial dimension of focal adhesion proteins from oxidative-stress-induced senescent cells with nanometer precision, and compares these to unstressed cells. We influenced cytoskeletal tension and the functioning of mechanosensitive ion channels using drugs and studied the combined effect of senescence and drug intervention on the focal adhesion structure. We found that H2O2-induced restructuring of the focal adhesion complex indicates a loss of tension and altered talin complexation. Mass spectroscopy-based proteomics confirmed the differential regulation of several cytoskeletal proteins induced by H2O2 treatment.

Novel interaction partners of the TPR/MET tyrosine kinase.

A large variety of biological processes is mediated by stimulation of the receptor tyrosine kinase MET. Screening a mouse embryo cDNA library, we were able to identify several novel, putative intracellular TPR/MET-substrates: SNAPIN, DCOHM, VAV-1, Sorting nexin 2, Death associated protein kinase 3, SMC-1, Centromeric protein C, and hTID-1. Interactions as identified by yeast two-hybrid analysis were validated in vitro and in vivo by mammalian two-hybrid studies, a far-western assay and coimmunoprecipitation. Participation in apoptosis-regulating mechanisms through interaction with DAPK-3 and cell cycle control via binding to nuclear proteins such as CENPC and SMC-1 are possible new aspects of intracellular MET signaling.

Multicolor karyotype analyses of mouse embryonic stem cells.

The manipulation of embryonic stem (ES) cells to introduce directional genetic changes into the genome of mice has become an important tool in biomedical research. Monitoring of cell morphology before and after DNA manipulation and special culture conditions are a prerequisite to preserve the pluripotent properties of ES cells and thus their ability to generate chimera and effective germline transmission (GLT). It has been reported that prolonged cell culturing may affect the diploid chromosomal composition of cells and therefore the percentage of chimerism and GLT. Herein, we report multicolor-fluorescence in situ hybridization (M-FISH) analysis of four different ES cell lines/clones. Although the morphology of all four ES cell lines/clones appeared normal and all four expressed the early markers Oct-3/4 and Nanog, two cell lines presented consistent numerical and structural chromosome aberrations. We demonstrate that M-FISH is a sensitive and accurate method for a comprehensive karyotype analysis of ES cells and may minimize time, costs, and disappointments due to inadequate ES cell sources.

Size and composition of T-cell receptor delta (TCRD) junctional sequences are not predictive of the sensitivity of clonospecific oligonucleotides designed for detection of minimal residual disease in acute lymphoblastic leukemia.

We characterized 168 junctional regions of T-cell receptor delta (TCRD) rearrangements from 116 children with acute lymphoblastic leukemia (ALL) (101 with precursor B-cell ALL, 15 with T-cell ALL). Application of 101 allele-specific oligonucleotide (ASO) probes representing 85 Vdelta2Ddelta3, 10 Ddelta2Ddelta3, 3 Vdelta1Jdelta1, 1 Vdelta3Jdelta1, and 2 Ddelta2Jdelta1 junctions for the detection of minimal residual disease (MRD) revealed detection levels of 10(-4) to 10(-6) leukemia cells in the vast majority of cases (93 of 101). Of interest was that neither the N, D, P (nontemplated, diversity, palindromic) content and length of the junctional regions nor the number of nucleotides deleted from the flanking V, D, or J (variable, diversity, joining) elements correlated with the sensitivity of ASO probes. These data indicated that in ALL TCRD rearrangements can serve as suitable tools for the detection of MRD irrespective of the specific composition of the junctional region.

Identification of cholesterol-regulating genes by targeted RNAi screening.

Elevated plasma cholesterol levels are considered responsible for excess cardiovascular morbidity and mortality. Cholesterol in plasma is tightly controlled by cholesterol within cells. Here, we developed and applied an integrative functional genomics strategy that allows systematic identification of regulators of cellular cholesterol levels. Candidate genes were identified by genome-wide gene-expression profiling of sterol-depleted cells and systematic literature queries. The role of these genes in cholesterol regulation was then tested by targeted siRNA knockdown experiments quantifying cellular cholesterol levels and the efficiency of low-density lipoprotein (LDL) uptake. With this strategy, 20 genes were identified as functional regulators of cellular cholesterol homeostasis. Of these, we describe TMEM97 as SREBP target gene that under sterol-depleted conditions localizes to endo-/lysosomal compartments and binds to LDL cholesterol transport-regulating protein Niemann-Pick C1 (NPC1). Taken together, TMEM97 and other factors described here are promising to yield further insights into how cells control cholesterol levels.

Activation of gef-h1, a guanine nucleotide exchange factor for RhoA, by DNA transfection.

Several oncogenes isolated by the NIH/3T3 transformation assay, i.e., dbl, dbs, lbc, lfc, lsc, net, ost and tim, contain a Dbl homology (DH) and a pleckstrin-homology (PH) domain and act as GEFs (guanine nucleotide exchange factors) for Rho-like GTPases. In a search for genes with oncogenic potential in DNA from the monocytic leukaemia cell line U937, we identified an amino-terminal truncated form of gef-h1, a gene encoding a GEF for RhoA. These data support the idea that a systematic search for mutations and/or deletions of GEFs in human cancer is promising.