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Mário C BarrosoJúnior Guilherme P Esteves Thiago P Nunes Lucia MG Silva Alvaro CD Faria Pedro L Melo 《Biomedical engineering online》2011,10(1):14
Introduction
A novel system that combines a compact mobile instrument and Internet communications is presented in this paper for remote evaluation of tremors. The system presents a high potential application in Parkinson's disease and connects to the Internet through a TCP/IP protocol. Tremor transduction is carried out by accelerometers, and the data processing, presentation and storage were obtained by a virtual instrument. The system supplies the peak frequency (fp), the amplitude (Afp) and power in this frequency (Pfp), the total power (Ptot), and the power in low (1-4 Hz) and high (4-7 Hz) frequencies (Plf and Phf, respectively). 相似文献113.
The developmental origins of adult health and disease (DOHaD) hypothesis that argues for a causal relationship between under-nutrition during early life and increased risk for a range of diseases in adulthood is gaining epidemiological support. One potential mechanism mediating these effects is the modulation of epigenetic markings, specifically DNA methylation. Since folate is an important methyl donor, alterations in supply of this micronutrient may influence the availability of methyl groups for DNA methylation. We hypothesised that low folate supply in utero and post-weaning would alter the DNA methylation profile of offspring. In two separate 2 × 2 factorial designed experiments, female C57Bl6/J mice were fed low- or control/high-folate diets during mating, and through pregnancy and lactation. Offspring were weaned on to either low- or control/high-folate diets, resulting in 4 treatment groups/experiment. Genomic DNA methylation was measured in the small intestine (SI) of 100-day-old offspring. In both experiments, SI genomic DNA from offspring of low-folate-fed dams was significantly hypomethylated compared with the corresponding control/high folate group (P = 0.009/P = 0.006, respectively). Post-weaning folate supply did not affect SI genomic DNA methylation significantly. These observations demonstrate that early life folate depletion affects epigenetic markings, that this effect is not modulated by post-weaning folate supply and that altered epigenetic marks persist into adulthood. 相似文献
114.
Laura C. Greaves Joanna L. Elson Marco Nooteboom John P. Grady Geoffrey A. Taylor Robert W. Taylor John C. Mathers Thomas B. L. Kirkwood Doug M. Turnbull 《PLoS genetics》2012,8(11)
Human ageing has been predicted to be caused by the accumulation of molecular damage in cells and tissues. Somatic mitochondrial DNA (mtDNA) mutations have been documented in a number of ageing tissues and have been shown to be associated with cellular mitochondrial dysfunction. It is unknown whether there are selective constraints, which have been shown to occur in the germline, on the occurrence and expansion of these mtDNA mutations within individual somatic cells. Here we compared the pattern and spectrum of mutations observed in ageing human colon to those observed in the general population (germline variants) and those associated with primary mtDNA disease. The pathogenicity of the protein encoding mutations was predicted using a computational programme, MutPred, and the scores obtained for the three groups compared. We show that the mutations associated with ageing are randomly distributed throughout the genome, are more frequently non-synonymous or frameshift mutations than the general population, and are significantly more pathogenic than population variants. Mutations associated with primary mtDNA disease were significantly more pathogenic than ageing or population mutations. These data provide little evidence for any selective constraints on the occurrence and expansion of mtDNA mutations in somatic cells of the human colon during human ageing in contrast to germline mutations seen in the general population. 相似文献
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Bailey TJ El-Hodiri H Zhang L Shah R Mathers PH Jamrich M 《The International journal of developmental biology》2004,48(8-9):761-770
The paired-like homeobox-containing gene Rx has a critical role in the eye development of several vertebrate species including Xenopus, mouse, chicken, medaka, zebrafish and human. Rx is initially expressed in the anterior neural region of developing embryos, and later in the retina and ventral hypothalamus. Abnormal regulation or function of Rx results in severe abnormalities of eye formation. Overexpression of Rx in Xenopus and zebrafish embryos leads to overproliferation of retinal cells. A targeted elimination of Rx in mice results in a lack of eye formation. Mutations in Rx genes are the cause of the mouse mutation eyeless (ey1), the medaka temperature sensitive mutation eyeless (el) and the zebrafish mutation chokh. In humans, mutations in Rx lead to anophthalmia. All of these studies indicate that Rx genes are key factors in vertebrate eye formation. Because these results cannot be easily reconciled with the most popular dogmas of the field, we offer our interpretation of eye development and evolution. 相似文献
118.
Karlsson M Mathers J Dickinson RJ Mandl M Keyse SM 《The Journal of biological chemistry》2004,279(40):41882-41891
MAP kinase phosphatase (MKP)-3 is a cytoplasmic dual specificity protein phosphatase that specifically binds to and inactivates the ERK1/2 MAP kinases in mammalian cells. However, the molecular basis of the cytoplasmic localization of MKP-3 or its physiological significance is unknown. We have used MKP-3-green fluorescent protein fusions in conjunction with leptomycin B to show that the cytoplasmic localization of MKP-3 is mediated by a chromosome region maintenance-1 (CRM1)-dependent nuclear export pathway. Furthermore, the nuclear translocation of MKP-3 seen in the presence of leptomycin B is mediated by an active process, indicating that MKP-3 shuttles between the nucleus and cytoplasm. The amino-terminal noncatalytic domain of MKP-3 is both necessary and sufficient for nuclear export of the phosphatase and contains a single functional leucine-rich nuclear export signal (NES). Even though this domain of the protein also mediates the binding of MKP-3 to MAP kinase, we show that mutations of the kinase interaction motif which abrogate ERK2 binding do not affect MKP-3 localization. Conversely, mutation of the NES does not affect either the binding or phosphatase activity of MKP-3 toward ERK2, indicating that the kinase interaction motif and NES function independently. Finally, we demonstrate that the ability of MKP-3 to cause the cytoplasmic retention of ERK2 requires both a functional kinase interaction motif and NES. We conclude that in addition to its established function in the regulated dephosphorylation and inactivation of MAP kinase, MKP-3 may also play a role in determining the subcellular localization of its substrate. Our results reinforce the idea that regulatory proteins such as MKP-3 may play a key role in the spatio-temporal regulation of MAP kinase activity. 相似文献
119.
Microbial diversity and complexity in hypersaline environments: A preliminary assessment 总被引:4,自引:0,他引:4
The microbial communities in solar salterns and a soda lake have been characterized using two techniques: BIOLOG, to estimate
the metabolic potential, and amplicon length heterogeneity analysis, to estimate the molecular diversity of these communities.
Both techniques demonstrated that the halophilic Bacteria and halophilic Archaea populations in the Eilat, Israel saltern
are dynamic communities with extensive metabolic potentials and changing community structures. Halophilic Bacteria were detected
in Mono Lake and the lower salinity ponds at the Shark Bay saltern in Western Australia, except when the crystallizer samples
were stressed by exposure to Acid Green Dye #9899. At Shark Bay, halophilic Archaea were found only in the crystallizer samples.
These data confirm both the metabolic diversity and the phylogenetic complexity of the microbial communities and assert the
need to develop more versatile media for the cultivation of the diversity of bacteria in hypersaline environments. Journal of Industrial Microbiology & Biotechnology (2002) 28, 48–55 DOI: 10.1038/sj/jim/7000175
Received 20 May 2001/ Accepted in revised form 15 June 2001 相似文献
120.