280 research outputs found

    Apraxia and motor dysfunction in corticobasal syndrome

    Get PDF
    Background: Corticobasal syndrome (CBS) is characterized by multifaceted motor system dysfunction and cognitive disturbance; distinctive clinical features include limb apraxia and visuospatial dysfunction. Transcranial magnetic stimulation (TMS) has been used to study motor system dysfunction in CBS, but the relationship of TMS parameters to clinical features has not been studied. The present study explored several hypotheses; firstly, that limb apraxia may be partly due to visuospatial impairment in CBS. Secondly, that motor system dysfunction can be demonstrated in CBS, using threshold-tracking TMS, and is linked to limb apraxia. Finally, that atrophy of the primary motor cortex, studied using voxel-based morphometry analysis (VBM), is associated with motor system dysfunction and limb apraxia in CBS.   Methods: Imitation of meaningful and meaningless hand gestures was graded to assess limb apraxia, while cognitive performance was assessed using the Addenbrooke's Cognitive Examination - Revised (ACE-R), with particular emphasis placed on the visuospatial subtask. Patients underwent TMS, to assess cortical function, and VBM.   Results: In total, 17 patients with CBS (7 male, 10 female; mean age 64.4+/2 6.6 years) were studied and compared to 17 matched control subjects. Of the CBS patients, 23.5% had a relatively inexcitable motor cortex, with evidence of cortical dysfunction in the remaining 76.5% patients. Reduced resting motor threshold, and visuospatial performance, correlated with limb apraxia. Patients with a resting motor threshold <50% performed significantly worse on the visuospatial sub-task of the ACE-R than other CBS patients. Cortical function correlated with atrophy of the primary and pre-motor cortices, and the thalamus, while apraxia correlated with atrophy of the pre-motor and parietal cortices.   Conclusions: Cortical dysfunction appears to underlie the core clinical features of CBS, and is associated with atrophy of the primary motor and pre-motor cortices, as well as the thalamus, while apraxia correlates with pre-motor and parietal atrophy

    Fractional flow reserve in patients with intermediate values of Duke Treadmill Score and borderline coronary lesions

    Get PDF
    Despite the wide usage of exercise ECG tests and Duke Treadmill Score (DTS) in clinical practice, no comparison between this scoring system and Fractional Flow Reserve (FFR) has yet been made, particularly in cases of angiographically verified borderline lesions. Thirty patients with single coronary lesions and angiographically assessed borderline stenosis (between 30-70%) and previously calculated intermediate values of DTS between -10 to +4 were examined using FFR. Adequate specificity and sensitivity (0.769 and 0.556, respectively) were in a more narrow range of -0.5 to -10. Sex and age did not have an influence on the DTS values. There was a correlation between the values of FFR and age (r=0.395, p=0.031) and between angiographic assessment of stenosis and quantitative coronary angiography (QCA) (r=0.648, p<0.0001). In the study population, a decision on revascularization could not be based solely on angiographic or QCA assessment of the artery or on the values of DTS

    SMAC is expressed de novo in a subset of cervical cancer tumors

    Get PDF
    BACKGROUND: Smac/Diablo is a recently identified protein that is released from mitochondria after apoptotic stimuli. It binds IAPs, allowing caspase activation and cell death. In view of its activity it might participate in carcinogenesis. In the present study, we analyzed Smac expression in a panel of cervical cancer patients. METHODS: We performed semi quantitative RT-PCR on 41 cervical tumor and 6 normal tissue samples. The study included 8 stage I cases; 16 stage II; 17 stage III; and a control group of 6 samples of normal cervical squamous epithelial tissue. RESULTS: Smac mRNA expression was below the detection limit in the normal cervical tissue samples. In contrast, 13 (31.7%) of the 41 cervical cancer biopsies showed detectable levels of this transcript. The samples expressing Smac were distributed equally among the stages (5 in stage I, 4 in stage II and 4 in stage III) with similar expression levels. We found no correlation between the presence of Smac mRNA and histology, menopause, WHO stage or disease status. CONCLUSIONS: Smac is expressed de novo in a subset of cervical cancer patients, reflecting a possible heterogeneity in the pathways leading to cervical cancer. There was no correlation with any clinical variable

    A Transcription Factor Map as Revealed by a Genome-Wide Gene Expression Analysis of Whole-Blood mRNA Transcriptome in Multiple Sclerosis

    Get PDF
    Background: Several lines of evidence suggest that transcription factors are involved in the pathogenesis of Multiple Sclerosis (MS) but complete mapping of the whole network has been elusive. One of the reasons is that there are several clinical subtypes of MS and transcription factors that may be involved in one subtype may not be in others. We investigate the possibility that this network could be mapped using microarray technologies and contemporary bioinformatics methods on a dataset derived from whole blood in 99 untreated MS patients (36 Relapse Remitting MS, 43 Primary Progressive MS, and 20 Secondary Progressive MS) and 45 age-matched healthy controls. Methodology/Principal Findings: We have used two different analytical methodologies: a non-standard differential expression analysis and a differential co-expression analysis, which have converged on a significant number of regulatory motifs that are statistically overrepresented in genes that are either differentially expressed (or differentially co-expressed) in cases and controls (e.g., VKROXQ6,p−value,3.31E−6;VKROX_Q6, p-value ,3.31E-6; VCREBP1_Q2, p-value ,9.93E-6, V$YY1_02, p-value ,1.65E-5). Conclusions/Significance: Our analysis uncovered a network of transcription factors that potentially dysregulate several genes in MS or one or more of its disease subtypes. The most significant transcription factor motifs were for the Early Growth Response EGR/KROX family, ATF2, YY1 (Yin and Yang 1), E2F-1/DP-1 and E2F-4/DP-2 heterodimers, SOX5, and CREB and ATF families. These transcription factors are involved in early T-lymphocyte specification and commitment as well as in oligodendrocyte dedifferentiation and development, both pathways that have significant biological plausibility in MS causation

    Antitumor and antiangiogenic effect of the dual EGFR and HER-2 tyrosine kinase inhibitor lapatinib in a lung cancer model

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>There is strong evidence demonstrating that activation of epidermal growth factor receptors (EGFRs) leads to tumor growth, progression, invasion and metastasis. Erlotinib and gefitinib, two EGFR-targeted agents, have been shown to be relevant drugs for lung cancer treatment. Recent studies demonstrate that lapatinib, a dual tyrosine kinase inhibitor of EGFR and HER-2 receptors, is clinically effective against HER-2-overexpressing metastatic breast cancer. In this report, we investigated the activity of lapatinib against non-small cell lung cancer (NSCLC).</p> <p>Methods</p> <p>We selected the lung cancer cell line A549, which harbors genomic amplification of EGFR and HER-2. Proliferation, cell cycle analysis, clonogenic assays, and signaling cascade analyses (by western blot) were performed <it>in vitro</it>. <it>In vivo </it>experiments with A549 cells xenotransplanted into nude mice treated with lapatinib (with or without radiotherapy) were also carried out.</p> <p>Results</p> <p>Lapatinib dramatically reduced cell proliferation (<it>P </it>< 0.0001), DNA synthesis (<it>P </it>< 0.006), and colony formation capacity (<it>P </it>< 0.0001) in A549 cells <it>in vitro</it>. Furthermore, lapatinib induced G1 cell cycle arrest (<it>P </it>< 0.0001) and apoptotic cell death (<it>P </it>< 0.0006) and reduced cyclin A and B1 levels, which are regulators of S and G2/M cell cycle stages, respectively. Stimulation of apoptosis in lapatinib-treated A549 cells was correlated with increased cleaved PARP, active caspase-3, and proapoptotic Bak-1 levels, and reduction in the antiapoptic IAP-2 and Bcl-xL protein levels. We also demonstrate that lapatinib altered EGFR/HER-2 signaling pathways reducing p-EGFR, p-HER-2, p-ERK1/2, p-AKT, c-Myc and PCNA levels. <it>In vivo </it>experiments revealed that A549 tumor-bearing mice treated with lapatinib had significantly less active tumors (as assessed by PET analysis) (<it>P </it>< 0.04) and smaller in size than controls. In addition, tumors from lapatinib-treated mice showed a dramatic reduction in angiogenesis (<it>P </it>< 0.0001).</p> <p>Conclusion</p> <p>Overall, these data suggest that lapatinib may be a clinically useful agent for the treatment of lung cancer.</p
    • …
    corecore