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91.
Advances in wearable technology allow for the objective assessment of motor performance in both in-home and in-clinic environments and were used to explore motor impairments in Parkinson’s disease (PD). The aims of this study were to: 1) assess differences between in-clinic and in-home gait speed, and sit-to-stand and stand-to-sit duration in PD patients (in comparison with healthy controls); and 2) determine the objective physical activity measures, including gait, postural balance, instrumented Timed-up-and-go (iTUG), and in-home spontaneous physical activity (SPA), with the highest correlation with subjective/semi-objective measures, including health survey, fall history (fallers vs. non-fallers), fear of falling, pain, Unified Parkinson''s Disease Rating Scale, and PD stage (Hoehn and Yahr). Objective assessments of motor performance were made by measuring physical activities in the same sample of PD patients (n = 15, Age: 71.2±6.3 years) and age-matched healthy controls (n = 35, Age: 71.9±3.8 years). The association between in-clinic and in-home parameters, and between objective parameters and subjective/semi-objective evaluations in the PD group was assessed using linear regression-analysis of variance models and reported as Pearson correlations (R). Both in-home SPA and in-clinic assessments demonstrated strong discriminatory power in detecting impaired motor function in PD. However, mean effect size (0.94±0.37) for in-home measures was smaller compared to in-clinic assessments (1.30±0.34) for parameters that were significantly different between PD and healthy groups. No significant correlation was observed between identical in-clinic and in-home parameters in the PD group (R = 0.10–0.25; p>0.40), while the healthy showed stronger correlation in gait speed, sit-to-stand duration, and stand-to-sit duration (R = 0.36–0.56; p<0.03). This suggests a better correlation between supervised and unsupervised motor function assessments in healthy controls compared to PD group. In the PD group, parameters related to velocity and range-of-motion of lower extremity within gait assessment (R = 0.58–0.84), and turning duration and velocity within iTUG test (R = 0.62–0.77) demonstrated strong correlations with PD stage (p<0.01). 相似文献
92.
Hilary C. Rees Voichita Ianas Patricia McCracken Shannon Smith Anca Georgescu Tirdad Zangeneh Jane Mohler Stephen A. Klotz 《Journal of visualized experiments : JoVE》2013,(77)
A simple, validated protocol consisting of a battery of tests is available to identify elderly patients with frailty syndrome. This syndrome of decreased reserve and resistance to stressors increases in incidence with increasing age. In the elderly, frailty may pursue a step-wise loss of function from non-frail to pre-frail to frail. We studied frailty in HIV-infected patients and found that ~20% are frail using the Fried phenotype using stringent criteria developed for the elderly1,2. In HIV infection the syndrome occurs at a younger age.HIV patients were checked for 1) unintentional weight loss; 2) slowness as determined by walking speed; 3) weakness as measured by a grip dynamometer; 4) exhaustion by responses to a depression scale; and 5) low physical activity was determined by assessing kilocalories expended in a week''s time. Pre-frailty was present with any two of five criteria and frailty was present if any three of the five criteria were abnormal.The tests take approximately 10-15 min to complete and they can be performed by medical assistants during routine clinic visits. Test results are scored by referring to standard tables. Understanding which of the five components contribute to frailty in an individual patient can allow the clinician to address relevant underlying problems, many of which are not evident in routine HIV clinic visits. 相似文献
93.
WooJhon Choi Kathrin J. Mohler Benjamin Potsaid Chen D. Lu Jonathan J. Liu Vijaysekhar Jayaraman Alex E. Cable Jay S. Duker Robert Huber James G. Fujimoto 《PloS one》2013,8(12)
We demonstrate in vivo choriocapillaris and choroidal microvasculature imaging in normal human subjects using optical coherence tomography (OCT). An ultrahigh speed swept source OCT prototype at 1060 nm wavelengths with a 400 kHz A-scan rate is developed for three-dimensional ultrahigh speed imaging of the posterior eye. OCT angiography is used to image three-dimensional vascular structure without the need for exogenous fluorophores by detecting erythrocyte motion contrast between OCT intensity cross-sectional images acquired rapidly and repeatedly from the same location on the retina. En face OCT angiograms of the choriocapillaris and choroidal vasculature are visualized by acquiring cross-sectional OCT angiograms volumetrically via raster scanning and segmenting the three-dimensional angiographic data at multiple depths below the retinal pigment epithelium (RPE). Fine microvasculature of the choriocapillaris, as well as tightly packed networks of feeding arterioles and draining venules, can be visualized at different en face depths. Panoramic ultra-wide field stitched OCT angiograms of the choriocapillaris spanning ∼32 mm on the retina show distinct vascular structures at different fundus locations. Isolated smaller fields at the central fovea and ∼6 mm nasal to the fovea at the depths of the choriocapillaris and Sattler''s layer show vasculature structures consistent with established architectural morphology from histological and electron micrograph corrosion casting studies. Choriocapillaris imaging was performed in eight healthy volunteers with OCT angiograms successfully acquired from all subjects. These results demonstrate the feasibility of ultrahigh speed OCT for in vivo dye-free choriocapillaris and choroidal vasculature imaging, in addition to conventional structural imaging. 相似文献
94.
Nitric oxide (NO) has been reported to act both as a destructive and a protective agent in the pathogenesis of the injuries
that occur during hypoxia/reoxygenation (H/R). It has been suggested that this dual role of NO depends directly on the isoform
of NO synthase (NOS) involved. In this work, we investigate the role that NO derived from endothelial NOS (eNOS) plays in
cardiac H/R-induced injury. Wistar rats were submitted to H/R (hypoxia for 30 min; reoxygenation of 0 h, 12 h and 5 days),
with or without prior treatment using the selective eNOS inhibitor l-NIO (20 mg/kg). Lipid peroxidation, apoptosis and protein nitration, as well as NO production (NOx), were analysed. The results
showed that l-NIO administration lowered NOx levels in all the experimental groups. However, no change was found in the lipid peroxidation
level, the percentage of apoptotic cells or nitrated protein expression, implying that eNOS-derived NO may not be involved
in the injuries occurring during H/R in the heart. We conclude that l-NIO would not be useful in alleviating the adverse effects of cardiac H/R. 相似文献
95.
96.
Thomas J. Simmons Kyle E. Mohler Claire Holland Florence Goubet Lenka Franková Douglas R. Houston Andrew D. Hudson Frank Meulewaeter Stephen C. Fry 《The Plant journal : for cell and molecular biology》2015,83(5):753-769
Cell walls are metabolically active components of plant cells. They contain diverse enzymes, including transglycanases (endotransglycosylases), enzymes that ‘cut and paste’ certain structural polysaccharide molecules and thus potentially remodel the wall during growth and development. Known transglycanase activities modify several cell‐wall polysaccharides (xyloglucan, mannans, mixed‐linkage β‐glucan and xylans); however, no transglycanases were known to act on cellulose, the principal polysaccharide of biomass. We now report the discovery and characterization of hetero‐trans‐β‐glucanase (HTG), a transglycanase that targets cellulose, in horsetails (Equisetum spp., an early‐diverging genus of monilophytes). HTG is also remarkable in predominantly catalysing hetero‐transglycosylation: its preferred donor substrates (cellulose or mixed‐linkage β‐glucan) differ qualitatively from its acceptor substrate (xyloglucan). HTG thus generates stable cellulose–xyloglucan and mixed‐linkage β‐glucan–xyloglucan covalent bonds, and may therefore strengthen ageing Equisetum tissues by inter‐linking different structural polysaccharides of the cell wall. 3D modelling suggests that only three key amino acid substitutions (Trp → Pro, Gly → Ser and Arg → Leu) are responsible for the evolution of HTG's unique specificity from the better‐known xyloglucan‐acting homo‐transglycanases (xyloglucan endotransglucosylase/hydrolases; XTH). Among land plants, HTG appears to be confined to Equisetum, but its target polysaccharides are widespread, potentially offering opportunities for enhancing crop mechanical properties, such as wind resistance. In addition, by linking cellulose to xyloglucan fragments previously tagged with compounds such as dyes or indicators, HTG may be useful biotechnologically for manufacturing stably functionalized celluloses, thereby potentially offering a commercially valuable ‘green’ technology for industrially manipulating biomass. 相似文献
97.
The small-subunit ribosomal RNA gene sequences from the hypotrichous ciliates Oxytricha nova and Stylonychia pustulata 总被引:17,自引:0,他引:17
We have determined the complete nucleotide sequence of the small- subunit
ribosomal RNA genes for the ciliate protozoans Stylonychia pustulata and
Oxytricha nova. The sequences are homologous and sufficiently similar that
these organisms must be closely related. In a phylogeny inferred from
comparisons of several eukaryotic small-subunit ribosomal RNAs, the
divergence of the ciliates from the eukaryotic line of descent is seen to
coincide with the radiation of the plants, the animals, and the fungi. This
radiation is preceded by the divergence of the slime mold, Dictyostelium
discoideum.
相似文献
98.
Balla S Thapar V Verma S Luong T Faghri T Huang CH Rajasekaran S del Campo JJ Shinn JH Mohler WA Maciejewski MW Gryk MR Piccirillo B Schiller SR Schiller MR 《Nature methods》2006,3(3):175-177
In addition to large domains, many short motifs mediate functional post-translational modification of proteins as well as protein-protein interactions and protein trafficking functions. We have constructed a motif database comprising 312 unique motifs and a web-based tool for identifying motifs in proteins. Functional motifs predicted by MnM can be ranked by several approaches, and we validated these scores by analyzing thousands of confirmed examples and by confirming prediction of previously unidentified 14-3-3 motifs in EFF-1. 相似文献
99.
Nucleotide sequence analysis of the lemur beta-globin gene family: evidence for major rate fluctuations in globin polypeptide evolution 总被引:1,自引:0,他引:1
Lemur beta-related globin genes have been isolated and sequenced. Orthology
of prosimian and human epsilon-, gamma-, and beta-related globin genes was
established by dot-matrix analysis. All of these lemur globin genes
potentially encode functional beta-related globin polypeptides, though
precisely when the gamma-globin gene is expressed remains unknown. The
organization of the 18-kb brown lemur beta-globin gene cluster (5'
epsilon-gamma-[psi eta-delta]-beta 3') is consistent with its evolution by
contraction via unequal crossing-over from the putative ancestral mammalian
beta-globin gene cluster (5' epsilon-gamma- eta-delta-beta 3'). The dwarf
lemur nonadult globin genes are arranged as in the brown lemur. Similar
levels of synonymous (silent) nucleotide substitutions and noncoding DNA
sequence differences have accumulated between species in all of these
genes, suggesting a uniform rate of noncoding DNA divergence throughout
primate beta-globin gene clusters. These differences are comparable with
those observed in the nonfunctional psi eta pseudogene and have therefore
accumulated at the presumably maximal neutral rate. In contrast,
nonsynonymous (replacement) nucleotide substitutions show a significant
heterogeneity in distribution for both the same gene in different lineages
and different genes in the same lineage. These major fluctuations in
replacement but not silent substitution rates cannot be attributed to
changes in mutation rate, suggesting that changes in the rate of globin
polypeptide evolution in primates is not governed solely by variable
mutation rates.
相似文献
100.