25 research outputs found
Validity of a novel computerized cognitive battery for mild cognitive impairment
BACKGROUND: The NeuroTrax Mindstreams computerized cognitive assessment system was designed for widespread clinical and research use in detecting mild cognitive impairment (MCI). However, the capability of Mindstreams tests to discriminate elderly with MCI from those who are cognitively healthy has yet to be evaluated. Moreover, the comparability between these tests and traditional neuropsychological tests in detecting MCI has not been examined. METHODS: A 2-center study was designed to assess discriminant validity of tests in the Mindstreams Mild Impairment Battery. Participants were 30 individuals diagnosed with MCI, 29 with mild Alzheimer's disease (AD), and 39 healthy elderly. Testing was with the Mindstreams battery and traditional neuropsychological tests. Receiver operating characteristic (ROC) analysis was used to examine the ability of Mindstreams and traditional measures to discriminate those with MCI from cognitively healthy elderly. Between-group comparisons were made (Mann-Whitney U test) between MCI and healthy elderly and between MCI and mild AD groups. RESULTS: Mindstreams outcome parameters across multiple cognitive domains significantly discriminated among MCI and healthy elderly with considerable effect sizes (p < 0.05). Measures of memory, executive function, visual spatial skills, and verbal fluency discriminated best, and discriminability was at least comparable to that of traditional neuropsychological tests in these domains. CONCLUSIONS: Mindstreams tests are effective in detecting MCI, providing a comprehensive profile of cognitive function. Further, the enhanced precision and ease of use of these computerized tests make the NeuroTrax system a valuable clinical tool in the identification of elderly at high risk for dementia
The impact of new research technologies on our understanding of environmental causes of disease: the concept of clinical vulnerability
In spite of decades of epidemiological research, the etiology and causal patterns for many common diseases, such as breast and colon cancer or neurodegenerative diseases, are still largely unknown. Such chronic diseases are likely to have an environmental origin. However, "environmental" risks have been often elusive in epidemiological studies. This is a conundrum for current epidemiological research. On the other side, the relative contribution of genes to chronic diseases, as emerging from GWAS, seems to be modest (15-50% increase in disease risk). What is yet to be explored extensively is a model of disease based on long-term effects of low doses of environmental exposures, incorporating both genetic and acquired susceptibility ("clinical vulnerability"), and the cumulative effects of different exposures. Such a disease model would be compatible with the weak associations found by GWAS and the still elusive role of many (low-level) environmental exposures. We also propose that the introduction of "-omic" high-throughput technologies, such as transcriptomics, proteomics and metabolomics, may provide, in the next years, powerful tools to investigate early effects of environmental exposures and understand the etiology of common diseases better, according to the "clinical vulnerability model". The development of "-omics", in spite of current limitations and lack of sound validation, could greatly contribute to the elucidation of the disease model we propose
The YEATS domain of Taf14 in Saccharomyces cerevisiae has a negative impact on cell growth
The role of a highly conserved YEATS protein motif is explored in the context of the Taf14 protein of Saccharomyces cerevisiae. In S. cerevisiae, Taf14 is a protein physically associated with many critical multisubunit complexes including the general transcription factors TFIID and TFIIF, the chromatin remodeling complexes SWI/SNF, Ino80 and RSC, Mediator and the histone modification enzyme NuA3. Taf14 is a member of the YEATS superfamily, conserved from bacteria to eukaryotes and thought to have a transcription stimulatory activity. However, besides its ubiquitous presence and its links with transcription, little is known about Taf14’s role in the nucleus. We use structure–function and mutational analysis to study the function of Taf14 and its well conserved N-terminal YEATS domain. We show here that the YEATS domain is not necessary for Taf14’s association with these transcription and chromatin remodeling complexes, and that its presence in these complexes is dependent only on its C-terminal domain. Our results also indicate that Taf14’s YEATS domain is not necessary for complementing the synthetic lethality between TAF14 and the general transcription factor TFIIS (encoded by DST1). Furthermore, we present evidence that the YEATS domain of Taf14 has a negative impact on cell growth: its absence enables cells to grow better than wild-type cells under stress conditions, like the microtubule destabilizing drug benomyl. Moreover, cells expressing solely the YEATS domain grow worser than cells expressing any other Taf14 construct tested, including the deletion mutant. Thus, this highly conserved domain should be considered part of a negative regulatory loop in cell growth
Transcriptomes of <i>Trypanosoma brucei</i> rhodesiense from sleeping sickness patients, rodents and culture:Effects of strain, growth conditions and RNA preparation methods
All of our current knowledge of African trypanosome metabolism is based on results from trypanosomes grown in culture or in rodents. Drugs against sleeping sickness must however treat trypanosomes in humans. We here compare the transcriptomes of Trypanosoma brucei rhodesiense from the blood and cerebrospinal fluid of human patients with those of trypanosomes from culture and rodents. The data were aligned and analysed using new user-friendly applications designed for Kinetoplastid RNA-Seq data. The transcriptomes of trypanosomes from human blood and cerebrospinal fluid did not predict major metabolic differences that might affect drug susceptibility. Usefully, there were relatively few differences between the transcriptomes of trypanosomes from patients and those of similar trypanosomes grown in rats. Transcriptomes of monomorphic laboratory-adapted parasites grown in in vitro culture closely resembled those of the human parasites, but some differences were seen. In poly(A)-selected mRNA transcriptomes, mRNAs encoding some protein kinases and RNA-binding proteins were under-represented relative to mRNA that had not been poly(A) selected; further investigation revealed that the selection tends to result in loss of longer mRNAs