[Study on the design and detection method of a novel blood pressure measurement system].

A novel blood pressure measurement system was designed which based on auscultatory method. And the electret sensor that embedded into the internal instrument can detect the Korotkoff-sound signal directly which is coupled by the cuff and transmitted in the cross connection. The BP values identification algorithm is based on combined detection of Korotkoff-sound and pulse signal, and the products of amplitudes and energies are calculated as the characteristic values of Korotkoff-sound, and the Korotkoff-sound phases are classified and detected by means of clustering of characteristic values, and then BP parameters are determined. The contrast test and statistical analysis showed good consistency and accuracy between the new BP detection method and conventional mercury sphygmomanometer.

[Risk evaluation of myocardial infarction based on multivariate trend analysis].

This paper is aimed to study the feasibility of myocardial infarction risk assessment by noninvasive multivariable trend analysis, including heart rate variability (HRV), deceleration capacity (DC) of heart rate and pulse wave velocity (PWV). Thirty five patients with cardiovascular diseases (11 Myocardial infarction (MI), 8 coronary artery disease (CAD), 6 artery atherosclerosis (AA) and 10 hypertension), and 31 healthy subjects were randomly selected into a control group for this research as comparison. 15 min ECG and 1 min pulse wave data were collected based on the analysis workbench developed by our Lab. HRV, DC and PWV between the cardiovascular group and the control group were analyzed and compared. The results showed that the HRV indices, DC and PWV were significantly higher than those in the control group. The DC and the HRV indices including NN50, PNN50 and TINN especially presented a decline trend that was consistent with the regularity of cardiovascular development process. This noninvasive multivariable trend analysis of HRV, DC and PWV can be a reference for the earlier risk prediction of MI.

[Mental fatigue assessment based on physiological signals].

OBJECTIVE: To assess mental fatigue by noninvasive monitoring of the physiological signals. METHODS: The changes in the physiological parameters including the electrodermal activity, heart rate and heart rate variability were analyzed in 14 subjects performing the reaction-time tasks when fatigue and changes in the reaction time occurred. RESULTS: The average skin conductance level, average heart rate, and heart rate variability parameters including the total power density, percentage of the very low power density, percentage of high power density all differed significantly between the sober state and the mental fatigue state. CONCLUSION: Monitoring the physiological parameters including the electrodermal activity, heart rate and heart rate variability is a noninvasive, effective and practical approach to mental fatigue assessment.

[Design and realization of a microarray data analysis platform].

OBJECTIVE: To design a platform for microarray data analysis and processing in the browser/server mode running in Linux operating system. METHODS: Based on the Apache HTTP server, the platform, programmed with Perl language, integrated R language and Bioconductor packages for processing and analysis of the input data of oligonucleotide arrays and two-color spotted arrays. Users were allowed to submit data and parameter configurations to the platform via the web page, and the results of analysis were also returned via the web page. RESULTS: With an easy operation and high performance, the platform fulfilled the functions of processing, quality assessment, biological annotation and statistical analysis of the data from oligonucleotide arrays and two-color spotted arrays. Using the platform, we analyzed the gene expression profiles in Mtb-stimulated macrophages of three clinical phenotypes, namely latent TB (LTB), pulmonary (PTB) and meningeal (TBM), and obtained valuable clues for identifying tuberculosis susceptibility genes. We also analyzed the effect of INH treatment on Mycobacterium tuberculosis gene expression in various dormancy models, such as hypoxia and KatG mutant, and found that a set of genes responded to INH treatment during exponential growth but not in dormancy, and that the overall number of differentially regulated genes was reduced in the cells in low metabolic state. CONCLUSION: The platform we have constructed integrates comprehensive resources, and with a user-friendly interface, allows direct result visualization to facilitate microarray data analysis.

[The design of data transfer protocol for home and community tele-medical system].

This article describes a design of physiological signal storage format and transfer protocol for the tele-medical system between home and community. The protocol is based on ASCII character, with frames as its basic structure. There are two kinds of frames: control frames and data frames. Control frames can start and stop data transfer, confirm the order, and ask for start. There are seven kinds of data frames, according to the different data types. Data is transferred in data frames. The protocol described in this article is simple and extensible. The design target has been accomplished in real system.

[Design and construction of the platform for comparative genomics].

OBJECTIVE: To design a versatile genome comparison and visualization platform based on browser/server mode supported by a local server. METHODS: The server of the platform was Apache HTTP server. Perl was used to integrate such genome alignment package and algorithms as MUMmer, LAGAN, and Mauve for different comparison purposes, and the users could submit data and parameters to the platform via the web page. The results of analysis were also returned via the web page. RESULTS: The platform could handle multiple data input formats, compare complete and draft genome sequence, alignment pair-wise or multi genome of more divergent species, identify regions of high similarity, locate local nucleotide mutations and large-scale recombination, and display the results by visualization interface. Analysis of the homology of 10 new strains of influenza A virus indicated that PB1 gene might evolve from human H3N2 viruses, PB2 and PA genes from avian H3N2 viruses, and HA and NS genes from swine H1N1 viruses. Alignment of Mycobacterium tuberculosis (H37Rv, CDC1551) and Mycobacterium bovis (AF2122/97) genomes revealed that sequence insertion/deletion and duplication were the major source of genomic differences. CONCLUSION: The platform integrate comprehensive resources with a user-friendly interface and intuitive result visualization to facilitate conventional study of comparative genomics.

A calibrated method for blood pressure measurement based on volume pulse wave / 中国医疗器械杂志

Physiology parameters measurement based on volume pulse wave is suitable for the monitoring blood pressure continuously. This paper described that the systolic blood pressure (SBP) and diastolic blood pressure (DBP) can be calibrated by measuring the pulse propagation time, just on one point of finger tip. The volume pulse wave was acquired by lighting the red and infrared LED alternately, and after signal processing, an accelerated pulse wave was obtained. Then by measuring the pulse wave propagation time between the progressive wave and reflected wave, we can find the relationship of the time and the blood pressure, and establish the related systolic blood pressure measurement equation. At the same time, based on the relationship between alternating current and direct current components in the volume pulse waveforms and through regression analysising, the relevant diastolic blood pressure measurement equation can be established. 33 clinical experimentation cases have been worked by dividing them into two groups: training group (18 cases) and control group (15 cases), by comparing with the measuring results of the OMRON electronic sphygmomanometer. The results indicated that the two methods had good coherence. The measurement described is simple and reliable, and may be served as a new method for noninvasively and continuously measurement of blood pressure.

[A novel respiratory detecting system based on bio-impedance].

This paper introduces the design and implementation of a novel respiratory detecting system based on bio-impedance method. By increasing electrodes in space, the system make multi-channel respiratory signals be superpositioned and filtered (SNR); Traditional filter methods by both hardware and software are also used to further increase anti-interference ability. A low consumption and portable instrument is designed based on MSP430 Micro Controller Unit (MCU), The experiment shows a better performance in the reduction of interference noises of heartbeat and blood flow especially the motion artifact. Also the system works stably.

[A study on the individual adaptability of electronic sphygmomanometer].

This paper analyzed the limitation of electronic sphygmomanometer based on oscillometry, and according to the characteristics of pulse signal, the author proposed a new method of the characteristic parameter detection based on wavelet transform, and improved its recognition ability on fixed-scale, via resampling rate according to the heartbeat. And the prototype test has been proved that this method is more adaptability for individuals and stability for operation.

Microarray analysis of gene expression in the ovarian cancer cell line HO-8910 with silencing of the ZNF217 gene.

Zinc-finger protein 217 (ZNF217), which is overexpressed during cancer progression, can promote tumor cell immortalization. To examine the function of ZNF217, a global expression profile was carried out using Affymetrix Gene Chip analysis with HG-U133 plus 2.0 arrays in the ovarian cancer cell line HO-8910 after silencing of the ZNF217 gene. The results were analyzed using the Gene Ontology program to investigate the functional network affected by ZNF217 in ovarian cancer cells. Changes in the mRNA expression of the affected genes were confirmed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The results showed that the ZNF217 gene is a key regulator of ovarian cancer, as the silencing of ZNF217 resulted in significant down-regulation by at least 8-fold of 164 genes in the HO-8910 cell line compared to non-silenced control cells. Among these down-regulated genes were ALOX15, CD1D, FXYD3, GAS6, KRT4, LIN7B, MMP-24, PDZK1, PEX6, PRSS8, SLC2A9, STRN and WFDC2. Down-regulation was confirmed by real-time RT-PCR after the silencing of ZNF217 (p<0.05). The results suggest that ZNF217 plays a central role in malignant processes in ovarian cancer.

Differential expression profiles of microRNAs in NIH3T3 cells in response to UVB irradiation.

MicroRNAs (miRNAs) are known as a kind of small, noncoding RNA, which play an important role in mediating many biological processes such as development, cell proliferation and differentiation in plants and animals. Here we report the differential expression profiles of miRNAs and characterized putative target genes in NIH3T3 cells at a series of different time points after UVB irradiation (compared with no UVB irradiation). The relative expression of mature miRNA genes was determined by miRNA microarray technique and the results were confirmed by real-time reverse transcriptase polymerase chain reaction (qRT-PCR). Potential target genes of these miRNAs were classified into different function categories with the GOstat software (http://gostat.wehi.edu.au/cgi-bin/goStat.pl). Several miRNAs in this study expressed highly at different time points, especially mmu-miR-365 and mmu-miR-21. Three miRNAs were lowly expressed, of which mmu-miR-465 showed low levels of expression at all time points, whereas after 50 J m(-2) UVB irradiation mmu-miR-296 and mmu-miR-376c showed low levels of expression at 6 and 12 h, respectively. Our study provided a basis for the global characterization of UV-regulated miRNA expression.

Evidence of gene conversion in the evolutionary process of the codon 41/42 (-CTTT) mutation causing beta-thalassemia in southern China.

The 4-bp deletion (-CTTT) at codon 41/42 (CD41/42) of the human beta-globin gene represents one of the most common beta-thalassemia mutations in East Asia and Southeast Asia, which is historically afflicted with endemic malaria, thus hypothetically evolving under natural selection by malaria infection. To understand the evolutionary process of generating the beta(CD41/42) allele and its maintenance, including the effect of natural selection on the pattern of linkage disequilibrium (LD), we sequenced a 15.933-kb region spanning 20.693 kb of the beta-globin cluster surrounding the 4-bp deletion using a sample from a Chinese population consisting of 24 normal individuals and 16 heterozygotes for the deletion. Forty-nine polymorphic sites were found. Analysis of the data, using a variety of methods including formal population genetics analysis and visual approaches, suggests that the spread of the CD41/42 (-CTTT) deletion is most likely mediated by interallelic gene conversion, although independent deletions in different lineages are also possible. The neutrality test resulted in a significant positive Tajima's D for the beta-globin locus, which is consistent with the existence of balancing selection. This suggests that the 4-bp deletion that occurred at this locus may be an event that is subject to natural selection, due to malaria, which leads to the heterozygote advantage, spread widely with further help by conversion and migration. The evolutionary process of this mutant through gene conversion that could conceivably take place between the 4-bp deletion and the normal sequence in the respective region is discussed in detail.

Electrocardiogram waveforms for monitoring effectiveness of chest compression during cardiopulmonary resuscitation.

BACKGROUND: Newer guidelines address the importance of effective chest compressions, citing evidence that this primary intervention is usually suboptimally performed during cardiopulmonary resuscitation. We therefore sought a readily available option for monitoring the effectiveness of chest compressions, specifically using the electrocardiogram. METHODS AND RESULTS: Ventricular fibrillation was induced by coronary artery occlusion and untreated for 5 mins. Male domestic pigs weighing 40 +/- 2 kg were randomized to optimal or suboptimal chest compressions after onset of ventricular fibrillation. Optimal depth of mechanical compression in six animals was defined as a decrease of 25% in anterior posterior diameter of the chest during compression. Suboptimal compression, also in six animals, was defined as a decrease of 17.5% in anterior posterior diameter. For each group, the chest compressions were maintained at a rate of 100 per min. After 3 mins of chest compression, defibrillation was attempted with a 150-J biphasic shock. All animals had return of spontaneous circulation after optimal compressions. This contrasted with suboptimal compressions, after which none of the animals had return of spontaneous circulation. Amplitude spectrum area values, representing the electrocardiographic amplitude frequency spectral area computed from conventional precordial leads, like coronary perfusion pressure and end tidal PCO2, were predictive of outcomes. CONCLUSION: The effectiveness of chest compressions was reflected in the amplitude spectrum area values. Accordingly, the amplitude spectrum area predictor may be incorporated in current automated external defibrillators to monitor and prompt the effectiveness of chest compression during cardiopulmonary resuscitation.

[A novel model of the medical instrumentation--an overview of wearable sensors and systems].

The traditional medical instrumentation is now not suited for the transformation of the present healthcare model. It's an attempt to make a breakthrough on traditions to develop wearable sensors/systems. Five articles about wearable technology are selected by this special topic. And our aim is to inspire the designers of medical devices to grasp the chance and to take a vigorous action on innovatory developments, so as to satisfy the huge requirements of the healthcare market, and to open a new era of the medical device industry.

[The design of a wearable ECG and respiration sensor vest and its monitoring system].

This article describes the design of a sensor vest and its corresponding measuring and transfering system which can be used for ECG and respiration monitoring in mobile and noninvasive conditions. The electric conduction textile is sutured in the inside of the vest in its specific position to be detecting electrodes, which are connected to the vest edge. The signal is then connected to the measuring and transferring system. in which the microcontroller and circuits monitor the ECG, heart rate and respiration data. The data are transmitted through the serial communication to a PC, and then are received and displayed with Visual Basic program.

Mathematical model of phosphatidylinositol-4,5-bisphosphate hydrolysis mediated by epidermal growth factor receptor generating diacylglycerol.

Phosphatidylinositol-4,5-bisphosphate (PIP2) is hydrolyzed in response to the tyrosine phosphorylation of the epidermal growth factor receptor (EGFR) and plays an important role in regulating cell proliferation and differentiation through the generation of second messengers diacylglycerol (DAG) and trisphosphate inositol (IP3) which lead to the activation of protein kinase C (PKC) and increased levels of intracellular calcium, respectively. In the paper, a mathematical model was established to simulate the accumulation of DAG due to PIP2 hydrolysis mediated by EGFR. Molecular mechanisms between DAG, PIP2, EGFR and phosphatidylinositol transfer protein (PITP) were explained successfully, and positive cooperativity which existed between phospholipase C-gamma1 (PLC-gamma1) and PIP2 was also explained. In the model the effects of parameters on simulation of PIP2 hydrolysis were analyzed and the efficacies of some molecular intervention strategies were predicted. To test the coherence between the model and the biological response to epidermal growth factor (EGF) in cells, the levels of DAG and the tyrosine phosphorylation-EGFRs in NIH3T3 mouse embryonic fibroblast (MEF) were determined by biochemical experiments which showed that the accumulation of DAG was a sigmoidal function of phosphorylation-EGFR concentration, and the consistency between the mathematical model and experimental results was confirmed. In brief, this mathematical model provided a new idea for the further study of the dynamic change of biological characteristics in inositol phospholipid hydrolysis, predicting the efficacy of molecular intervention and the relationship between the metabolisms of inositol phospholipid and other signal transduction pathways.

[Research on EMD and its application in biomedical signal processing].

In this paper a new technique, Empirical Mode Decomposition(EMD), for use in non-stationary and non-linear data processing, was introduced. Some simulated signal, real ECG and RRI signals combined with Hilbert Transform method were analyzed. The authors also put emphasis on the differences between EMD and Wavelet Transform.

[Analysis and realization of the method for predicting physical pathways of allosteric communication in a protein family].

A fundamental goal in signal transduction study is to understand allosteric communication. The authors present hereby a statistical coupling analysis method (developed by Steve W. Lockless etc.) for quantitative mapping of the global network of amino acid positions in a protein and predicting a set of energetically coupled positions, which may constitute the physical pathways of allosteric communication in a protein family. Based on MATLAB, the authors realized this method and created histograms of amino acid distributions for all 63 395 entries (as of April 2004) in the Swiss-Prot database of eukaryotic proteins and calculated the mean values. The result was similar to that calculated by Steve W. Lockless in October 1998.

[Value of galvanic skin response in assessment of diabetic autonomic neuropathy].

OBJECTIVE: To explore a method for early detection of diabetic autonomic neuropathy (DAN) on the basis of analysis of galvanic skin response (GSR). METHODS: In 25 randomly selected diabetic inpatients (14 with clinical DAN symptoms), GSR signals were collected from the fingers of both hands based on Virtual Instrumental WorkBench-LabVIEW and compared with those acquired from normal subjects. RESULTS: The GSR indices of patients either with or without DAN were different from those of normal subjects, and even in the same patients, the changes of these indices after clinical treatment were also obvious. CONCLUSION: GSR detection and analysis can help understand the impairment of the autonomic system and facilitate DAN assessment.

[Mathematical model of epidermal growth factor receptor-mediated lipid phosphatidylinositol(4,5)-bisphosphate hydrolyzation by phospholipase C-gamma1 activity].

OBJECTIVE: To investigate the dynamic characteristics of lipid phosphatidylinositol (4,5)-bisphosphate (PIP(2)) in plasma membrane hydrolyzed by phospholipase C-gamma1 in epidermal growth factor receptor(EGFR)-mediated signal pathway. METHODS: A mathematical model based on the law of mass action was established with differential equations to simulate metabolizable pathway of PIP(2). RESULTS: Differential equations of the key product concentration during hydrolysis of PIP(2) were formulated, and the effects of the parameters on these hydrolyzed products analyzed. CONCLUSION: This mathematical model provides foundation for further investigation of the dynamic changes of biological characteristics and the relations between the key product concentrations in PIP2 hydrolysis.