It is very important for pulmonary disease treatment to monitor the pulmonary function continuously. In this paper, the hardware of electrical impedance tomography (EIT) system is designed, and simulative model of human thorax is established for image reconstruction based on Landweber pre-iteration method. Compared with linear back projection, the method above results in the better image reconstruction with little trailing and increased speed of real-time reconstruction.

A complete Electrical Impedance Tomography system that can monitor lung function is introduced in this paper. The master PC is responsible for visual control and image reconstruction, while DSP carries out tasks such as electrode selection, data acquisition and data communication with the master. Based on the DDS technique, the exciting signal source has high accuracy, and the data can be acquired by phase-sensibility demodulation. The vivo experiment proves that gravity exerts an effect on the distribution of intrapulmonary ventilation, and shows that the Electrical Impedance Tomography is able to monitor lung circulation and check pathological changes.

In order to study the variation of complex impedance and characteristic parameters on human normal and tumor lung tissue during the extracorporeal time, we established a real part-imaginary part chart of complex impedance on lung tissue which provided the basic theory and the reference data for research on elementary medicine and clinical diagnosis of lung cancer and meanwhile provided prior information for electrical impedance tomography (EIT) research. In the experiment carried out in our laboratory, when operation was finished, we kept the lung cancer tissue and normal tissue neatly separated into the cylindrical testing cavities and kept the temperature and humidity at expected values. Then the measurements of complex impedance property are performed at frequency from 1 000 Hz to 30 MHz using 4294A impedance analyzer of Aglient Company. With time changing, the results showed that there was a significant change occurring on the complex impedance of human normal and tumor lung tissue. However, the impedance of normal lung tissue is greater than that of tumor lung tissue. We consider that this change should be related to the change in extracellular fluid, intracellular fluid and cell membrane.
Electric Impedance ; Humans ; Lung ; physiology ; Lung Neoplasms ; pathology ; Tomography

A master-slave electrical impedance tomography (EIT) system for body complex impedance based on digital signal processor (DSP) is designed in this paper. Used as the master computer, a PC performs the image reconstruction and display on time, while DSP carries out such tasks as electrode selection, data acquisition and data communication with the master. Based on DDS technique, the signal generator can create the sine wave signals, and it's amplitude, frequency and phase can be continuously adjusted. The designed feedback unit can improve the linearity and the stability of the voltage-controlled current source effectively. Undersampling technology and digital demodulation technology are used in this system in order to attain the information of real and imaginary components of the body complex impedance. Back projection method is adopted to reconstruct the image in this system. Experimental results show that this system improves the data acquisition speed and the image resolution.

Objective:Measured the soluble forms of intercellular adhesive molecule 1 (sICAM 1), soluble vascular cell adhesion molecule ( sVCAM 1) and interleukin 1(IL 1),tumor necrosis factor(TNF), interferon ?(IFN ?),study the role of sICAM 1 and sVCAM 1 in rheumatoid arthritis(RA).Methods:A sandwich ELISA technique was used to measure the serums levels of sICAM 1, sVCAM 1 ,IL 1,TNF,IFN ? in 30 patients with active RA and 30 normal control subjects.Results:The levels of sICAM 1 and sVCAM 1 in patients with RA were significantly higher than that in control subjects(P

Obiective To realize real-time data processing in lung ventilation reconstruction based on electrical impedance tomography(EIT). Methods The image reconstruction algorithms, plotting functions and matrix calculations are dynamic transferred with Matlab C++, Mathtools and VC++ to meet the requirements of data processing and imaging in real time.Results Image reconstruction and real-time data processing were realized successfully in lung ventilation based on EIT. Conclusion It provides a new strategy for real-time data processing of image reconstruction by EIT.

Objective To investigate the effects of inhibiting epithelial mesenchymal transition (EMT) on metastastic potential of hepatocellular carcinoma (HCC) enhanced by hepatic arterial occlusion in mice. Methods Using a metastatic human HCC orthotopic nude mice model (MHCC97),the effects of hepatic artery ligation (HAL) alone,combination of HAL and phosphatidylinositol 3-kinase (PI3K)inhibitor LY294002,or combination of HAL and interferon-α (IFN-α) on the growth of planted human HCC cells and pulmonary metastasis were evaluated,respectively.The cells and tumor tissues specimens were analyzed through expression of Akt,p-Akt,E-cadhein,N-cadherin and Twist. Results HAL inhibits tumor growth (2002.97 ± 331.28 ) mm3 vs.( 3921.23 ± 786.21 ) mm3,t =4.052,P ＜ 0.01 ),while promoting pulmonary metastatsis ( 10/12 vs.4/12,P ＜ 0.05).HAL combined with LY294002 represses significantly enhanced pulmonary metastasis rate by HAL alone (0/6 vs.6/6,P ＜ 0.01 ).Moderate-dose IFN-α (7.5 × 106 U/kg) combined with HAL failed to further reduce tumor volume compared with that of HAL alone,but inhibited markedly pulmonary metastasis (2/6 vs.6/6,P ＜ 0.05 ).The augmented level of N-cadherin and Twist in tumor tissues due to HAL reduced by LY294002 or 7.5 × 106 U/kg IFN-α.The arrest of EMT by LY294002 or IFN-α in HAL-treated xenografts was further demonstrated by the in vitro response of hypoxic cells to both agents. Conclusions Inhibition of EMT in HCC cells could repress enhanced metastastic potential due to hepatic arterial occlusion.

To investigate the effects of didannsine(ddI)on the morphological alterations of dorsal root ganglion(DRG)neurons,dissoci-ated DRG cells from rat embryo were studied.DRG cells were cultured for 3 days and then treated with ddI for additional 3 claysin differ-ent concentrations(1μg/ml,5 μg/ml,10μg/ml and 20 μg/ml,respectively).Afarthat,DRG cells were processedformicrotubule as-soeiated protein 2(MAP2)labeling and observed under confocal laser scanning microscopy(CLSM).The results showed that both thenumber and length of neurites of the DRG cells after exposed to ddl significantly down-regulated in a dose-dependentmanner compared withcontrol group,thus suggesting that ddI may have inhibitory effects on neufite regeneration and outgrowth in dissociated DRG cultures.

Objective To analyze the death causes of of dermatomyositis(DM)and polymyositis(PM)patients with interstitial pneumonia.Methods A retrospectively analysis of the clinical and laboratory characteristics of 15 dead DM and PM patients with interstitial pneumonia was carried out,and 23 survivors served as controls.Results The age of the dead group was(50.1?12.0)years old,and 12(80%)patients died within the six months after onset.The mortality was higher in the acute or subacute interstitial pneumonia patients than that in the chronic patients.With longer course of the disease,lung infections became the major cause of death.Significantly higher serum lactate dehydrogenase,glutamate- pyruvate transaminase,glutamic-oxalacetic transaminase levels were found in the dead group.The dead group had higher incidence of dyspnea and“Velcro”-like crackles and louer arterial oxygen pressure.The elevation of lactate dehydrogenase indicated worse prognosis.The elevation of creatine kinase and anti Jo-1 antibody werent the death causes. Conclusion The early onset of interstitial lung disease and lung infection were the major death causes in dermatomyositis and polymyositis patients.The earlier treatment of pneumonia-may improve the prognosis and reduce mortality.

Objective To evaluate the relationship between positive thyroid autoantibody and risk of preterm birth.Methods Literature search was done in PubMed,Embase,China Academic Journal Network Publishing Database,Wanfang Medical Database and China Biology Medicine disc databases from January 1st,1989 to January 26th,2012.Criteria for inclusion included:(1) Prospective cohort study; (2) The exposure was positive thyroid autoantibody and outcome was preterm birth; (3) The enrolled subjects were pregnant women without cardiovascular or rheumatic disease; (4) Relative risk (RR) and its 95％ confidence interval (95％CI) of preterm birth were provided in the study.Meta-analysis was performed by Stata 12.0.The relationship between positive thyroid autoantibody and risk of preterm birth was evaluated by RR and 95％ CI.Results Ten cohort studies were enrolled.One thousand six hundred and fifty seven cases of preterm birth occurred among 25 081 pregnant women.Heterogeneity among the 10 studies was found in meta-analysis (I2 =79.2％,P＜0.01).The risk of preterm birth in pregnant women with positive thyroid autoantibody was higher than those in control group by random effects analysis (RR=1.61,95％CI:1.18-2.20,P＜0.05).Subgroup analysis was further performed.In five studies,the cases of control group were pregnant women with normal thyroid function; heterogeneity was not found in these five studies (I2=39.1％,P=0.160); and RR of the risk of preterm birth was 2.55 in pregnant women with positive thyroid autoantibody (95 ％ CI:2.04 3.19,P＜0.01).In the other five studies,the cases of controlgroup were pregnant women who had not been ruled out the possibility of thyroid dysfunction;heterogeneity was not found in these five studies either (I2 =0.0％,P =0.970); and RR was 1.18(95 ％ CI:1.01-1.37,P＜0.05).After excluding two low-quality studies,RR of the risk of preterm birth was 1.72 in pregnant women with positive thyroid autoantibody (95％CI:1.18 2.53,P＜0.05).The funnel plots presented symmetrical graphics,indicating that there was no publication bias.Conclusions Positive thyroid autoantibody in pregnant women is a risk factor of preterm birth.