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21.
Guillaume Chouinard-Pelletier Mathieu Leduc David Guay Sylvain Coulombe Richard L Leask Elizabeth AV Jones 《Biomedical engineering online》2012,11(1):1-12
Background
Abnormal blood glucose (BG) concentrations have been associated with increased morbidity and mortality in both critically ill adults and infants. Furthermore, hypoglycaemia and glycaemic variability have both been independently linked to mortality in these patients. Continuous Glucose Monitoring (CGM) devices have the potential to improve detection and diagnosis of these glycaemic abnormalities. However, sensor noise is a trade-off of the high measurement rate and must be managed effectively if CGMs are going to be used to monitor, diagnose and potentially help treat glycaemic abnormalities.Aim
To develop a tool that will aid clinicians in identifying unusual CGM behaviour and highlight CGM data that potentially need to be interpreted with care.Methods
CGM data and BG measurements from 50 infants at risk of hypoglycaemia were used. Unusual CGM measurements were classified using a stochastic model based on the kernel density method and historical CGM measurements from the cohort. CGM traces were colour coded with very unusual measurements coloured red, highlighting areas to be interpreted with care. A 5-fold validation of the model was Monte Carlo simulated 25 times to ensure an adequate model fit.Results
The stochastic model was generated using ~67,000 CGM measurements, spread across the glycaemic range ~2-10?mmol/L. A 5-fold validation showed a good model fit: the model 80% confidence interval (CI) captured 83% of clinical CGM data, the model 90% CI captured 91% of clinical CGM data, and the model 99% CI captured 99% of clinical CGM data. Three patient examples show the stochastic classification method in use with 1) A stable, low variability patient which shows no unusual CGM measurements, 2) A patient with a very sudden, short hypoglycaemic event (classified as unusual), and, 3) A patient with very high, potentially un-physiological, glycaemic variability after day 3 of monitoring (classified as very unusual).Conclusions
This study has produced a stochastic model and classification method capable of highlighting unusual CGM behaviour. This method has the potential to classify important glycaemic events (e.g. hypoglycaemia) as true clinical events or sensor noise, and to help identify possible sensor degradation. Colour coded CGM traces convey the information quickly and efficiently, while remaining computationally light enough to be used retrospectively or in real-time. 相似文献22.
Günter EA Kapustina OM Popeyko OV Chelpanova TI Efimtseva EA Ovodov YS 《Biochemistry. Biokhimii?a》2008,73(7):826-832
Sodium salicylate (NaSA) increased induction of both intracellular and extracellular beta-1,3-glucanases in calluses of campion and duckweed. NaSA concentrations from 30 to 100 mM were optimal for induction of intracellular glucanase in the campion callus, and for induction of extracellular glucanase the optimal concentration varied from 5 to 100 mM. The glucanase activity in the duckweed callus was lower than in the campion callus, and co-cultivation of the campion callus with Trichoderma harzianum mycelium increased the production of intracellular and extracellular beta-1,3-glucanases and polygalacturonase in the callus. Biosynthesis by T. harzianum of glucanases, extracellular polygalacturonase and xylanase, and of intracellular galactosidase was increased. The co-cultivation was accompanied by increased activity of intracellular acidic isoform of glucanase Glu-3 secreted by the callus cells into the medium, whereas NaSA activated in the callus culture the extracellular acidic isoform Glu-1 and extracellular basic isoform Glu-5. These data indicate the induction of these isoforms and the specificity of protective response of plant cells to different factors. 相似文献
23.
Kolenchukova OA Akchebash SV Chizhmotria NM Parilova OV Kapustina TA Otto VS 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2008,(3):77-79
Quantitative and qualitative composition of microflora of nasal mucosa as well as carriage of staphylococci was assessed in patients with chronic and acute forms of maxillary sinusitis. Changes in microflora of nasal mucosa and presence of pathogenic and persistence-associated characteristics of staphylococci in both forms of maxillary sinusitis were revealed. Increase of resistance staphylococci to antibiotics in patients with chronic form of maxillary sinusitis was shown. 相似文献
24.
V. V. Garkavenko I. N. Karaban’ M. T. Kapustina L. I. Limanskaya 《Neurophysiology》1999,31(6):399-402
In 18 27- to 56-year-old tested subjects, we measured the latency of sensorimotor reactions (SMRL) and parameters of the somatosensory
evoked potentials (SSEP), related to these reactions, observed in two experimental paradigms. In test 1, every third stimulus
in a train of identical stimuli was considered the “necessary” signal, while in test 2, the subject had to select such a signal
from three different versions of the stimuli presented in a randomized manner. For each subject, we selectively averaged the
SSEP related to different (short and long) SMRL. We demonstrated the existence of different types of the dependences between
the SSEP parameters and the values of SMRL; the pattern of these dependences could be different in tests 1 and 2. For test
1, a negative dependence between the variations of SMRL and amplitude of the P100 SSEP component was observed, while test
2 results were characterized by a clearly expressed negative correlation between the SMRL, and N150 amplitude (P<0.05). Negative correlation between the SMRL and integral amplitude of the P100-N150-P250 complex (P<0.05) was a common manifestation of the dependence between the SMR and SSEP parameters observed under conditions of both
tests. We suppose that the dependences between the variations of SSEP parameters and SMRL values reflect changes in the level
of mobilization of attention and in the structure of the latter in the course of performance of a sensorimotor task. 相似文献
25.
26.
Narayan P Subramaniyam Outi RM Väisänen Katrina E Wendel Jaakko AV Malmivuo 《Nonlinear biomedical physics》2010,4(Z1):S4
Background
The electroencephalography (EEG) is an attractive and a simple technique to measure the brain activity. It is attractive due its excellent temporal resolution and simple due to its non-invasiveness and sensor design. However, the spatial resolution of EEG is reduced due to the low conducting skull. In this paper, we compute the potential distribution over the closed surface covering the brain (cortex) from the EEG scalp potential. We compare two methods – L-curve and generalised cross validation (GCV) used to obtain the regularisation parameter and also investigate the feasibility in applying such techniques to N170 component of the visually evoked potential (VEP) data.Methods
Using the image data set of the visible human man (VHM), a finite difference method (FDM) model of the head was constructed. The EEG dataset (256-channel) used was the N170 component of the VEP. A forward transfer matrix relating the cortical potential to the scalp potential was obtained. Using Tikhonov regularisation, the potential distribution over the cortex was obtained.Results
The cortical potential distribution for three subjects was solved using both L-curve and GCV method. A total of 18 cortical potential distributions were obtained (3 subjects with three stimuli each – fearful face, neutral face, control objects).Conclusions
The GCV method is a more robust method compared to L-curve to find the optimal regularisation parameter. Cortical potential imaging is a reliable method to obtain the potential distribution over cortex for VEP data.27.
28.
Zaozao Chen Elizabeth Lessey Matthew E. Berginski Li Cao Jonathan Li Xavier Trepat Michelle Itano Shawn M. Gomez Maryna Kapustina Cai Huang Keith Burridge George Truskey Ken Jacobson 《PloS one》2013,8(1)
The issue of how contractility and adhesion are related to cell shape and migration pattern remains largely unresolved. In this paper we report that Gleevec (Imatinib), an Abl family kinase inhibitor, produces a profound change in the shape and migration of rat bladder tumor cells (NBTII) plated on collagen-coated substrates. Cells treated with Gleevec adopt a highly spread D-shape and migrate more rapidly with greater persistence. Accompanying this more spread state is an increase in integrin-mediated adhesion coupled with increases in the size and number of discrete adhesions. In addition, both total internal reflection fluorescence microscopy (TIRFM) and interference reflection microscopy (IRM) revealed a band of small punctate adhesions with rapid turnover near the cell leading margin. These changes led to an increase in global cell-substrate adhesion strength, as assessed by laminar flow experiments. Gleevec-treated cells have greater RhoA activity which, via myosin activation, led to an increase in the magnitude of total traction force applied to the substrate. These chemical and physical alterations upon Gleevec treatment produce the dramatic change in morphology and migration that is observed. 相似文献
29.
V. G. Vilkov S. A. Shal’nova A. D. Deev S. S. Davydova A. V. Kapustina I. E. Koltunov 《Human physiology》2006,32(4):410-415
The materials of a cross-sectional and prospective Russian-US population study (the Russian Lipid Research Clinics Prevalence Study) have been used to develop models intended for estimating the probability of death from coronary heart disease, all cardiovascular disease, and all causes over 10 and 20 years. The prediction was performed by constructing artificial neural networks. Testing on an independent sample has shown an accuracy of 66–73%. 相似文献
30.
A. A. Kicha I. I. Kapustina N. V. Ivanchina A. I. Kalinovsky P. S. Dmitrenok V. A. Stonik N. V. Pal’yanova T. M. Pankova M. V. Starostina 《Russian Journal of Bioorganic Chemistry》2008,34(1):118-124
Two new steroid glycosides: distolasteroside D6, (24S)-24-O-(β-D-xylopyranosyl)-5α-cholestane-3β,6α,8,15β,16β,24-hexaol, and distolasteroside D7, (22E,24R)-24-O-(β-D-xylopyranosyl)-5α-cholest-22-ene-3β,6α,8,15β,24-pentaol were isolated along with the previously known distolasterosides D1, D2, and D3, echinasteroside C, and (25S)-5α-cholestane-3β4β,6α,7α,8,15α,16β,26-octaol from the Far Eastern starfish Distolasterias nipon. The structures of new compounds were elucidated by NMR spectroscopy and MALDI TOF mass spectrometry. Like neurotrophins, distolasterosides D1, D2, and D3 were shown to induce neuroblast differentiation in a mouse neuroblastoma C1300 cell culture. 相似文献