1
|
Wu YF, Yu YX, Guo CC, Chang CQ. [Research Progress on Application of Sports Beverage to Post-exercise Fluid Restoration]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2021; 43:928-935. [PMID: 34980333 DOI: 10.3881/j.issn.1000-503x.12756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A good hydration status is important to the exercise performance and cognitive function of exercisers.The effective restoration of fluid balance after exercise is helpful to prevent dehydration,maintain body fluid balance,accelerate fatigue recovery,and enhance exercise performance.As the most effective sports nutrition supplement,sports beverage has different ingredients and formulas,and also has various effects.To provide clues for the development of sports beverage,this article reviews the types,components,effects,and mechanisms of sports beverage currently used in post-exercise fluid restoration.
Collapse
Affiliation(s)
- Yi-Fan Wu
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Ying-Xiang Yu
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Cheng-Cheng Guo
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Cui-Qing Chang
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| |
Collapse
|
2
|
Wu YF, Huang XR, Yu YX, Guo CC, Xie L, Chang CQ. [Effect of the Seasonal Adaptability on Carbohydrate-electrolyte Beverage Efforts on Post-exercise Rehydration in Healthy Young Men]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2021; 43:716-726. [PMID: 34728032 DOI: 10.3881/j.issn.1000-503x.13609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Objective To compare the effects of carbohydrate-electrolyte beverage on post-exercise rehydration of healthy young men in different seasons,and to explore the influence of seasonal adaptability on fluid and electrolyte balance.Methods Fifteen healthy men,aged(24.4±0.5)years,completed 2 trails in a random crossover design both in summer and winter.During recovery,they consumed a drink volume equivalent to 100% of their sweat loss with plain boiled water(the water group)or carbohydrate-electrolyte beverage(the beverage group).Recovery was monitored for further 180 minutes by the collection of blood and urine samples.Results The dehydration time in summer was significantly shorter by about 20 minutes than that in winter(t=3.045,P=0.004).In summer,the fluid retention rate of the beverage group was significantly higher than that of the water group at 120 minutes after rehydration [(83.7±2.8)% vs.(73.7±3.7)%,F=5.312,P=0.028],and significantly higher than the water group at 180 minutes [(74.8±3.6)% vs.(66.1±4.3)%,F=4.340,P=0.046].In winter,the fluid retention rate of the beverage group at 180 minutes after rehydration was significantly higher than that of the water group [(74.9±4.7)% vs.(68.0±6.0)%,F=4.128,P=0.048].There was no significantly seasonal difference in the fluid retention effect of carbohydrate-electrolyte beverage at 180 minutes after rehydration.In the beverage group,the changes of blood glucose and serum sodium levels(all P<0.05)in summer were significantly higher than those in winter at 10-180 minutes after rehydration,and the fractional excretion of sodium in summer was significantly higher in summer than in winter at 120 and 180 minutes after rehydration(F120=4.972,P=0.034;F180=8.425,P=0.007);however,there was no significant difference in plasma osmolality(all P> 0.05).For the water group,the plasma osmolality in winter was lower than that in summer,while the degree of dryness and thirst was higher in winter than in summer.Conclusions Seasonal adaptability influenced the hydration status and its regulating factors.People dehydrated faster after exercise in summer than in winter,and the hydration status was relatively stable in winter.However,in summer,the blood glucose and electrolytes responded more rapidly to carbohydrate-electrolyte beverage supply,and the plasma osmolality and subjective perception recovered faster.Therefore,during the 180-minute recovery period,the carbohydrate-electrolyte beverage had a higher rehydration efficiency in a short recovery time in summer although there was no significantly seasonal difference in the fluid retention rate.
Collapse
Affiliation(s)
- Yi-Fan Wu
- Beijing Key Laboratory of Sports Injuries,Institute of Sports Medicine of Peking University, Department of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Xian-Ren Huang
- Beijing Key Laboratory of Sports Injuries,Institute of Sports Medicine of Peking University, Department of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Ying-Xiang Yu
- Beijing Key Laboratory of Sports Injuries,Institute of Sports Medicine of Peking University, Department of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Cheng-Cheng Guo
- Beijing Key Laboratory of Sports Injuries,Institute of Sports Medicine of Peking University, Department of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Lan Xie
- Beijing Key Laboratory of Sports Injuries,Institute of Sports Medicine of Peking University, Department of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Cui-Qing Chang
- Beijing Key Laboratory of Sports Injuries,Institute of Sports Medicine of Peking University, Department of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| |
Collapse
|
3
|
Zhang HL, Huo ZJ, Wang HN, Wang W, Chang CQ, Shi L, Li D, Li R, Qiao J. [Acupuncture ameliorates negative emotion in PCOS patients: a randomized controlled trial]. Zhongguo Zhen Jiu 2020; 40:385-90. [PMID: 32275367 DOI: 10.13703/j.0255-2930.20191231-k0005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To evaluate the effectiveness and possible mechanism of acupuncture treatment for negative emotion in patients with polycystic ovary syndrome (PCOS). METHODS A total of 40 PCOS patients were randomly divided into an observation group and a control group, 20 cases in each one. Both groups received lifestyle interventions (exercise and diet guidance) on the 5th day of menstruation. On the basis of above treatment, the patients in the observation group received acupuncture at Guanyuan (CV 4), Zhongwan (CV 12), Guilai (ST 29), Futu (ST 32), Liangqiu (ST 34), Sanyinjiao (SP 6), Zusanli (ST 36), Hegu (LI 4), Shenmen (HT 7), Baihui (GV 20) as the main acupoints, and connected the electroacupuncture (continuous wave, 2 Hz, 30 min), once every other day, 3 times a week. The treatment for 1 month was as one course and 4 courses were required totally in both groups. Before and after treatment, the body mass index (BMI), ferriman-gallway (F-G) score, self-rating anxiety scale (SAS) score, self-rating depression scale (SDS) score, PCOS health-related quality of life questionnaire (PCOSQ) score were observed, meanwhile, serum sex hormone, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen (E2), progestin (P), prolactin (PRL), testosterone (T), sex hormone-binding globulin (SHBG) and free androgen index (FAI) levels, and serumβ-endorphin levels were detected. RESULTS Compared with before treatment, the BMI, F-G score, SAS score, SDS score and serum FAI level were decreased and the PCOSQ score and the levels of serum SHBG andβ-endorphin were increased in the observation group after treatment (all P<0.05). Compared with before treatment, the SDS score was decreased in the control group after treatment (P<0.05). Compared with the control group, the F-G score, SDS score, SAS score, and serum FAI level were lower, and the PCOSQ score and serumβ-endorphin level were higher in the observation group after treatment (all P<0.05). CONCLUSION Applying acupuncture to the treatment of patients with PCOS can effectively relieve anxiety and depression, and the mechanism may be related to the regulation on the levels of serumβ-endorphin and androgen.
Collapse
Affiliation(s)
- Hao-Lin Zhang
- Department of TCM, Institute of Sports Medicine, Peking University Third Hospital, Beijing 100191, China
| | - Ze-Jun Huo
- Department of TCM, Peking University Third Hospital, Beijing 100191, China
| | - Hai-Ning Wang
- Department of Endocrinology, Peking University Third Hospital, Beijing 100191, China
| | - Wei Wang
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China
| | - Cui-Qing Chang
- Institute of Sports Medicine, Peking University Third Hospital, Beijing 100191, China
| | - Li Shi
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China
| | - Dong Li
- Department of TCM, Peking University Third Hospital, Beijing 100191, China
| | - Rong Li
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China
| | - Jie Qiao
- Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China
| |
Collapse
|
4
|
Yu YX, Chang CQ, Zhang XY, Guo CC. [Application of Internet-based Interventions in Weight Management]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 2018; 40:405-410. [PMID: 29978801 DOI: 10.3881/j.issn.1000-503x.2018.03.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Overweight and obesity are associated with a range of chronic diseases and have become a major global health concern. With the progress of Internet technology,electronic health care has emerged,providing new tools and Methods for weight management. Internet-based technology has shown certain effectiveness in facilitating interventions on overweight,obesity,and their associated diseases. This article reviews the recent advances in these interventions and evaluates their effectiveness,efficiency,and feasibility.
Collapse
Affiliation(s)
- Ying-Xiang Yu
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Cui-Qing Chang
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Xiao-Yuan Zhang
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| | - Cheng-Cheng Guo
- Institute of Sports Medicine,Peking University Third Hospital,Beijing 100191,China
| |
Collapse
|
5
|
Chang CQ. [Why new Dietary Guidelines for Americans canceled the limit consumption of dietary cholesterol?]. Zhonghua Nei Ke Za Zhi 2016; 55:586-588. [PMID: 27480548 DOI: 10.3760/cma.j.issn.0578-1426.2016.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
|
6
|
Dotson WD, Douglas MP, Kolor K, Stewart AC, Bowen MS, Gwinn M, Wulf A, Anders HM, Chang CQ, Clyne M, Lam TK, Schully SD, Marrone M, Feero WG, Khoury MJ. Prioritizing genomic applications for action by level of evidence: a horizon-scanning method. Clin Pharmacol Ther 2014; 95:394-402. [PMID: 24398597 PMCID: PMC4689130 DOI: 10.1038/clpt.2013.226] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 11/08/2013] [Indexed: 11/09/2022]
Abstract
As evidence accumulates on the use of genomic tests and other health-related applications of genomic technologies, decision makers may increasingly seek support in identifying which applications have sufficiently robust evidence to suggest they might be considered for action. As an interim working process to provide such support, we developed a horizon-scanning method that assigns genomic applications to tiers defined by availability of synthesized evidence. We illustrate an application of the method to pharmacogenomics tests.
Collapse
Affiliation(s)
- WD Dotson
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - MP Douglas
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- McKing Consulting Corporation, Atlanta, Georgia, USA
| | - K Kolor
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - AC Stewart
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- McKing Consulting Corporation, Atlanta, Georgia, USA
| | - MS Bowen
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - M Gwinn
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- McKing Consulting Corporation, Atlanta, Georgia, USA
| | - A Wulf
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- Cadence Group, Atlanta, Georgia, USA
| | - HM Anders
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- McKing Consulting Corporation, Atlanta, Georgia, USA
| | - CQ Chang
- Epidemiology and Genomics Research Program, National Cancer Institute, Bethesda, Maryland, USA
| | - M Clyne
- Epidemiology and Genomics Research Program, National Cancer Institute, Bethesda, Maryland, USA
- Kelly Services, Troy, Michigan, USA
| | - TK Lam
- Epidemiology and Genomics Research Program, National Cancer Institute, Bethesda, Maryland, USA
| | - SD Schully
- Epidemiology and Genomics Research Program, National Cancer Institute, Bethesda, Maryland, USA
| | - M Marrone
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - WG Feero
- Maine Dartmouth Family Medicine Residency Program, Augusta, Maine, USA
| | - MJ Khoury
- Office of Public Health Genomics, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- Epidemiology and Genomics Research Program, National Cancer Institute, Bethesda, Maryland, USA
| |
Collapse
|
7
|
Ioannidis JPA, Zhou Y, Chang CQ, Schully SD, Khoury MJ, Freedman AN. Potential increased risk of cancer from commonly used medications: an umbrella review of meta-analyses. Ann Oncol 2013; 25:16-23. [PMID: 24310915 DOI: 10.1093/annonc/mdt372] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Several commonly used medications have been associated with increased cancer risk in the literature. Here, we evaluated the strength and consistency of these claims in published meta-analyses. We carried out an umbrella review of 74 meta-analysis articles addressing the association of commonly used medications (antidiabetics, antihyperlipidemics, antihypertensives, antirheumatics, drugs for osteoporosis, and others) with cancer risk where at least one meta-analysis in the medication class included some data from randomized trials. Overall, 51 articles found no statistically significant differences, 13 found some decreased cancer risk, and 11 found some increased risk (one reported both increased and decreased risks). The 11 meta-analyses that found some increased risks reported 16 increased risk estimates, of which 5 pertained to overall cancer and 11 to site-specific cancer. Six of the 16 estimates were derived from randomized trials and 10 from observational data. Estimates of increased risk were strongly inversely correlated with the amount of evidence (number of cancer cases) (Spearman's correlation coefficient = -0.77, P < 0.001). In 4 of the 16 topics, another meta-analysis existed that was larger (n = 2) or included better controlled data (n = 2) and in all 4 cases there was no statistically significantly increased risk of malignancy. No medication or class had substantial and consistent evidence for increased risk of malignancy. However, for most medications we cannot exclude small risks or risks in population subsets. Such risks are unlikely to be possible to document robustly unless very large, collaborative studies with standardized analyses and no selective reporting are carried out.
Collapse
Affiliation(s)
- J P A Ioannidis
- Stanford Prevention Research Center, Department of Medicine and Department of Health Research and Policy, Stanford University School of Medicine, Stanford
| | | | | | | | | | | |
Collapse
|
8
|
Chang CQ, Chen YB, Chen ZM, Zhang LT. Effects of a carbohydrate-electrolyte beverage on blood viscosity after dehydration in healthy adults. Chin Med J (Engl) 2010; 123:3220-3225. [PMID: 21163119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
BACKGROUND The consumption of carbohydrate-electrolyte beverages (CEs) has been known to be more effective than plain water for recovery from dehydration. This phenomenon suggests that the ingestion of CEs after dehydration is better than water for maintaining body fluid and plasma volume, and for the recovery from hemoconcentration and high blood viscosity as well. High blood viscosity causes infarction and other cardiovascular events. In this study, CE was compared with water and tea for the ability to reduce increased blood viscosity after dehydration. METHODS A crossover random control study was conducted to assess the effectiveness of three beverages for rehydration and decreasing of blood viscosity. Following exercise-induced dehydration of 2.2% of body weight in a permanent warm environment, 10 male subjects rested in a thermoneutral environment for 3 hours (rehydration period, REP). The subjects ingested test beverages equal to their body weight loss during the first 20 minutes in REP. Blood and urine samples were obtained throughout the experiments to assess the rehydration effect. RESULTS The change in blood viscosity at a shear rate of 5/s was significantly lower in CE ((-1.66 ± 0.21) mPa×s) in comparison to water ((-0.95 ± 0.26) mPa×s) or tea ((-0.92 ± 0.14) mPa×s) at 60th minute during the REP. The fluid retention rate was significantly greater for CE ((77.0 ± 3.9)%) than water ((61.2 ± 3.4)%) and tea ((60.5 ± 3.7)%) for 3 hours of rest in REP. CONCLUSIONS The recovery from high blood viscosity induced by dehydration was higher with CE consumption than with water or tea. These results suggest that CE is useful for normalizing increased blood viscosity due to exercise-induced dehydration.
Collapse
Affiliation(s)
- Cui-Qing Chang
- Institute of Sports Medicine, Peking University Third Hospital, Beijing 100191, China.
| | | | | | | |
Collapse
|
9
|
Li SY, Chang CQ, Ma FY, Yu CL. Modulating effects of chlorogenic acid on lipids and glucose metabolism and expression of hepatic peroxisome proliferator-activated receptor-alpha in golden hamsters fed on high fat diet. Biomed Environ Sci 2009; 22:122-129. [PMID: 19618689 DOI: 10.1016/s0895-3988(09)60034-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To examine the effects of chlorogenic acid (CGA) on lipid and glucose metabolism under a high dietary fat burden and to explore the possible role of peroxisome proliferator-activated receptor-alpha (PPAR-alpha) in these effects. METHODS Twenty male golden hamsters were randomly divided into CGA treatment group (n=10, given peritoneal injection of CGA solution prepared with PBS, 80 mg CGA/kg body weight daily), and control group (n=10, given PBS i.p. at the average volume of the treatment group). Animals in both groups were given 15% high fat diet. Eight weeks after treatment with CGA, the level of biochemical parameters in fasting serum and tissues and the expression of hepatic mRNA and protein PPAR-alpha were determined. RESULTS Eight weeks after treatment with CGA, the levels of fasting serum triglyceride (TG), free fatty acid (FFA), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), glucose (FSG), and insulin (FSI) were significantly lower in the GGA treatment group than in the control group. CGA also led to higher activity of hepatic lipase (HL), lower contents of TG and FFA in liver, and lower activity of lipoprotein lipase (LPL) in skeletal muscle. Furthermore, CGA significantly elevated significantly elevated the expression level of mRNA and protein expression in hepatic PPAR-alpha. CONCLUSION CGA can modify lipids and glucose metabolism, which may be attributed to PPAR-alpha facilitated lipid clearance in liver and improved insulin sensitivity.
Collapse
Affiliation(s)
- Shu-Yuan Li
- Division of Nutrition and Biochemistry, Institute of Sports Medicine, Third Hospital, Peking University, Beijing 100191, China
| | | | | | | |
Collapse
|
10
|
Abstract
With the introduction of microarray, cancer classification, diagnosis and prediction are made more accurate and effective. However, the final outcome of the data analyses very much depend on the huge number of genes with relatively small number of samples present in each experiment. It is thus crucial to select relevant genes to be used for future specific cancer markers. Many feature selection methods have been proposed but none is able to classify all kinds of microarray data accurately, especially on those multi-class datasets. We propose a one-versus-one comparison method for selecting discriminatory features instead of performing the statistical test in a one-versus-all manner. Brain cancer is chosen as an example. Here, 3 types of statistics are used: signal-to-noise ratio (SNR), t-statistics and Pearson correlation coefficient. Results are verified by performing hierarchical and k-means clustering. Using our one-versus-one comparisons, best performance accuracies of 90.48% and 97.62% can be obtained by hierarchical and k-means clustering respectively. However best performance accuracies of 88.10% and 80.95% can be obtained respectively when using one-versus-all comparison. This shows that one-versus-one comparison is superior.
Collapse
Affiliation(s)
- Y Y Leung
- Dept. of Electr. & Electron. Eng., Hong Kong Univ.,. Hong Kong.
| | | | | | | |
Collapse
|
11
|
Abstract
Second order blind identification (SOBI) technique is a promising independent component analysis (ICA) method to extract somatosensory evoked potential (SEP). This simulation study focused on SEP extraction from EEG and power-line noise contaminated SEP signals at signal to noise ratio (SNR) of -10dB and -20dB. The correlation coefficients between template SEP and SOBI extracted SEP showed significant high similarity (r>0.76) at -10dB and mild acceptable similarity (r>0.6) at -20dB EEG contaminated SEP. However, SOBI extracted SEP showed good performance in power-line noise situation to achieve high correlation coefficients with template SEP (r=0.96). The fast extracted SEP showed stable amplitude and latency, which are almost identical with the SEP template. The results suggested that SOBI is an appropriate method to extract SEP from noisy background.
Collapse
Affiliation(s)
- Hongtao Liu
- Department of Orthopaedics and Traumatology, the University of Hong Kong, Pokfulam Road, Hong Kong.
| | | | | | | |
Collapse
|
12
|
Tang M, Chang CQ, Fung PCW, Chau KT, Chan FHY. An Improved Method for Discriminating ECG Signals using Typical Nonlinear Dynamic Parameters and Recurrence Quantification Analysis in Cardiac Disease Therapy. Conf Proc IEEE Eng Med Biol Soc 2007; 2005:2459-62. [PMID: 17282735 DOI: 10.1109/iembs.2005.1616966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The discrimination of ECG signals using nonlinear dynamic parameters is of crucial importance in the cardiac disease therapy and chaos control for arrhythmia defibrillation in the cardiac system. However, the discrimination results of previous studies using features such as maximal Lyapunov exponent (λ<inf>max</inf>) and correlation dimension (D<inf>2</inf>) alone are somewhat limited in recognition rate. In this paper, improved methods for computing λ<inf>max</inf>and D<inf>2</inf>are purposed. Another parameter from recurrence quantification analysis is incorporated to the new multi-feature Bayesian classifier with λ<inf>max</inf>and D<inf>2</inf>so as to improve the discrimination power. Experimental results have verified the prediction using Fisher discriminant that the maximal vertical line length (V<inf>max</inf>) from recurrence quantification analysis is the best to distinguish different ECG classes. Experimental results using the MIT-BIH Arrhythmia Database show improved and excellent overall accuracy (96.3%), average sensitivity (96.3%) and average specificity (98.15%) for discriminating sinus, premature ventricular contraction and ventricular flutter signals.
Collapse
Affiliation(s)
- M Tang
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, PRC.
| | | | | | | | | |
Collapse
|
13
|
Ting KH, Fung PCW, Chang CQ, Chan FHY. Automatic correction of artifact from single-trial event-related potentials by blind source separation using second order statistics only. Med Eng Phys 2006; 28:780-94. [PMID: 16406675 DOI: 10.1016/j.medengphy.2005.11.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2004] [Revised: 09/24/2005] [Accepted: 11/18/2005] [Indexed: 11/25/2022]
Abstract
Event-related potentials (ERP) are in general masked by various kinds of artifacts. To attenuate the effects of artifacts, various schemes have been introduced, such as epoch rejection, electro-oculogram (EOG) regression and independent component analysis (ICA). However, none of the existing techniques can automatically remove various kinds of artifacts from a single ERP epoch. EOG regression cannot handle artifacts other than ocular ones. ICA incorporating higher order statistics (HOS) normally requires data with large number of time samples in order that the solution is robust. In this paper we blindly separate the multi-channel ERP into source components by estimating the correlation matrices of the data. Since only second order statistics (SOS) is involved, the process performs well at the single epoch level. Automatic artifact identification is performed in the source domain by introducing objective criteria for various artifacts. Criteria are based on time domain signal amplitude for blink and spurious peak artifact, scalp distribution of signal power for eye movement artifact and power distribution of frequency components for muscle artifact. The correction procedure can be completed by removing the identified artifactual sources from the raw multi-channel ERP.
Collapse
Affiliation(s)
- K H Ting
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, HKSAR, PR China
| | | | | | | |
Collapse
|
14
|
Hu Y, Lam BSC, Chang CQ, Chan FHY, Lu WW, Luk KDK. Adaptive signal enhancement of somatosensory evoked potential for spinal cord compression detection: an experimental study. Comput Biol Med 2006; 35:814-28. [PMID: 16278110 DOI: 10.1016/j.compbiomed.2004.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2003] [Accepted: 07/19/2004] [Indexed: 11/29/2022]
Abstract
The objective of this study was to assess the efficacy of adaptive signal enhancement (ASE) as a means of indicating intraoperative spinal cord impingement. ASE technique was used to determine the changes in the somatosensory evoked potential (SEP) elicited from eighteen rats with varying levels of spinal cord compression. ASE technique was found to be able to effectively extract SEP signals for the detection of spinal cord injury. Furthermore, while the traditional ensemble averaging (EA) technique requires more than 500 trials for meaningful signal processing in severe noisy SEP recordings, the ASE method required only 50 trials to provide similar information. Because of its fast and reliable SEP detection, the ASE method is ideal for spinal cord monitoring in the clinical setting.
Collapse
Affiliation(s)
- Yong Hu
- Department of Orthopaedics & Traumatology, The University of Hong Kong, Duchess of Kent Children's Hospital, 12 Sandy Bay Road, Hong Kong, China.
| | | | | | | | | | | |
Collapse
|
15
|
Lam BSC, Hu Y, Lu WW, Luk KDK, Chang CQ, Qiu W, Chan FHY. Multi-adaptive filtering technique for surface somatosensory evoked potentials processing. Med Eng Phys 2005; 27:257-66. [PMID: 15694610 DOI: 10.1016/j.medengphy.2004.09.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2004] [Revised: 08/10/2004] [Accepted: 09/17/2004] [Indexed: 11/28/2022]
Abstract
Somatosensory evoked potential (SEP) testing has been widely applied to diagnosis of various neurological disorders. However, SEP recorded using surface electrodes is buried in noises, which makes the signal-to-noise ratio (SNR) very poor. Conventional averaging method usually requires up to thousands of raw SEP input trials to increase the SNR so that an identifiable waveform can be produced for latency and amplitude measurement. In this study, a multi-adaptive filtering (MAF) technique, emerging from the combination of well-developed adaptive noise canceller and adaptive signal enhancer, is introduced for fast and accurate surface SEP extraction. The MAF technique first processes the raw surface recorded SEP by the Canceller with a reference noise channel of background noise for adaptive subtraction before entering the Enhancer. The MAF was verified by filtering simulated SEP signals in which electroencephalography and Gaussian noise of different SNRs were added. It was found that the MAF could effectively suppress the noise and enhance the SEP components such that the SNR of the SEP is improved. Results showed that MAF with 50 input trials could provide similar performance in SEP detection to those extracted by the conventional averaging method with 1000 trials even at an SNR of -20 dB.
Collapse
Affiliation(s)
- Benny S C Lam
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam, Hong Kong
| | | | | | | | | | | | | |
Collapse
|
16
|
Abstract
In this paper, we propose a novel approach for electron paramagnetic resonance (EPR) mixture spectra analysis based on blind source separation (BSS) technique. EPR spectrum of a free radical is often superimposed by overlapping spectra of other species. It is important and challenging to accurately identify and quantify the 'pure' spectra from such mixtures. In this study, an automated BSS method implementing independent component analysis is used to extract the components from mixed EPR spectra that contain overlapping components of different paramagnetic centers. To apply this method, there is no requirement to know the component spectra or the number of components in advance. The method is applied to analyze free radical EPR spectra which are collected from standard chemical system, cultured cell suspense, and ex vivo rat kidneys by spin trapping EPR technique. Results show that the BSS method proposed here is capable of identifying the component EPR spectra from mixtures with unknown compositions. The BSS technique can offer powerful aids in resolving spectral overlapping problems in general EPR spectroscopy analysis.
Collapse
Affiliation(s)
- J Y Ren
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong
| | | | | | | | | |
Collapse
|