To investigate the effects of conducting electrodes implanted into the penicillin-induced epilepsy foci in rats on seizures, 30 male SD rats were randomly divided into experimental group (EG) and control group (CG). Afer penicillin(PNC) administration, metal electrode was implanted into the epilepsy focus in EG. Behavior evaluations were given after PNC injection in both groups and electroencephalogram recordings were taken respectively. Immunohistochemical methods were used to test the expressions of P38 and Calcium channel a 1A subunit (CACNA1A) at the serial time-point. We found that EG showed reduction of epileptic discharge frequency than did CG at time-point 3 h and 6 h, and that P38 expressions of EG were lower than those of CG in the injected side, and the expressions of Calcium channel a 1A subunit (CACNA1A) were downregulated in EG at time-point 6 h and 24 h. This evidence suggests that the metal electrode implanted into the penicillin-induced epilepsy focus may reduce the epileptic discharges and downregulate the expressions of P38 and CACNA1A. This new idea might be used in antiepileptic field in future.
Animals ; Calcium Channels ; metabolism ; Down-Regulation ; Electrodes, Implanted ; Electroencephalography ; Epilepsy ; chemically induced ; therapy ; Male ; Penicillins ; Rats ; Rats, Sprague-Dawley ; p38 Mitogen-Activated Protein Kinases ; metabolism

Using the present cone beam reconstruction formula for general trajectory, we have investigated the issue of detector efficiency for non-helical trajectory. The results reveal that the two factors dominating the detector efficiency are detector geometry and filtering directions. The methods for to higher detector efficiency are proposed, and the reliability and feasibility are tested by simulation results.
Cone-Beam Computed Tomography ; instrumentation ; methods ; Humans ; Image Processing, Computer-Assisted ; methods ; Radiographic Image Enhancement ; methods ; Scattering, Radiation ; X-Ray Intensifying Screens

In an ECG auto-analysis system, correct QRS detection is most important. For this detection there are several methods, such as derivative-based algorithms, filter-bank methods and wavelet based methods and neural network approaches, but there is no single method that is extensively used. These methods are compared and analyzed in this paper.
Algorithms ; Electrocardiography ; Humans ; Signal Processing, Computer-Assisted

This study sought to explore the relationship between the change in ventricular electrical remodeling caused by mechano-electrical feedback and the expression of L-type Ca2+ -channel and/or sarcoplasmic reticulum Ca2+ -ATPase in the rabbits with congestive heart failure (CHF). 138 rabbits were divided into two groups (CHF and control). We measured the ventricular monophasic action potential duration (MAPD) and ventricular effective refractory period (VERP) during ventricular pacing at the stimulus frequency of 220/240/260 bpm in these rabbits. Rapid atrial pacing (260/min) was given for 30 minutes. The MAPD and VERP were measured again. Then ventricular fibrillation was induced by S1S2S3 program stimulation. We extracted the total RNA from the myocardium respectively and detected L-type Ca2+ -channel mRNA and sarcoplasmic reticulum Ca2+ -ATPase mRNA by use of Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). In group CHF, with the increasing of preload/afterload, L-type Ca2+ -channel mRNA was up regulated after rapid atrial pacing when compared with that in control groups (P < 0.05). There was no significant change in sarcoplasmic reticulum Ca2+ -ATPase mRNA after rapid atrial pacing when compared with controls (P > or = 0.05). The changes in MAPD90 and VERP were related with the extent of L-type Ca2+ -channel mRNA up regulation. But the changes in MAPD90 and VERP were not significantly related with the extent of sarcoplasmic reticulum Ca2+ -ATPase mRNA up regulation. These findings suggest that Mechano-Electrical Feedback could increase the regional changes of ventricular electrical remodeling in rabbits with CHF and so to predispose them to ventricular arrhythmia. The changes may be related with the up regulation of L-type Ca2+ -channel mRNA, but not with sarcoplasmic reticulum Ca2+ -ATPase mRNA.
Action Potentials ; Animals ; Calcium Channels, L-Type ; genetics ; metabolism ; Cardiac Pacing, Artificial ; Electric Conductivity ; Electrophysiology ; Female ; Heart Failure ; metabolism ; physiopathology ; Male ; RNA, Messenger ; genetics ; metabolism ; Rabbits ; Random Allocation ; Refractory Period, Electrophysiological ; Sarcoplasmic Reticulum ; genetics ; metabolism ; Ventricular Remodeling

The method of event-related potentials (ERP) was used to study the gender difference in face recognition. The stimuli in the experiment were 10 upright and 10 inverted face photos. The subjects, half female and half male, were asked to judge whether the face was upright or inverted. The results showed that the N170 wave forms were observed in the occipito-temporal regions and they were found exhibiting brain's right hemispheric dominance. The stimuli of different gender photos were noticed to have no significant impact on the N170 wave forms, but there were significant differentce in the amplitude and latency period of N170 between different gender participants. Moreover, there was marked difference in the latency period of the male participants watching the same gender face and different gender face. Similar results were not found in the ERP's latency period of female participants.
Adult ; Brain ; physiology ; Electroencephalography ; Evoked Potentials ; Face ; Facial Expression ; Female ; Form Perception ; physiology ; Humans ; Male ; Pattern Recognition, Visual ; physiology ; Recognition (Psychology) ; Sex Factors ; Young Adult

The traditional clinical trail designs always depend on expert opinions and lack statistical evaluations. In this article, we present a method and illustrate how population parameter uncertainty may be incorporated in the overall simulation model. Using the techniques of clinical trail simulation (CTS) and setting up predictions on the basis of pharmacokinetics-pharmacodynamics (PK-PD) models, we advance the modeling methods for simulation, for treatment effects, and for the clinical trail power under the given PK-PD conditions. Then we discuss the model of uncertainty, suggest an ANOVA-based method, add eta2 statistics for sensitivity analysis, and canvass the effect of uncertainty about population parameters on clinical trail power. The results from simulations and the indices derived from this type of sensitivity analysis may be used for grading the influence on the prediction quality of uncertainty about different population parameters. The experiment results are satisfactory and the approach presented has practical value in clinical trails.
Algorithms ; Clinical Trials as Topic ; methods ; Computer Simulation ; Data Interpretation, Statistical ; Humans ; Models, Biological ; Monte Carlo Method ; Pharmacokinetics ; Pharmacology ; Uncertainty

GEP (Gene expression programming) is a new genetic algorithm, and it has been proved to be excellent in function finding. In this paper, for the purpose of setting up a diagnostic model, GEP is used to deal with the data of heart disease. Eight variables, Sex, Chest pain, Blood pressure, Angina, Peak, Slope, Colored vessels and Thal, are picked out of thirteen variables to form a classified function. This function is used to predict a forecasting set of 100 samples, and the accuracy is 87%. Other algorithms such as SVM (Support vector machine) are applied to the same data and the forecasting results show that GEP is better than other algorithms.
Algorithms ; Artificial Intelligence ; Computational Biology ; methods ; Data Mining ; Diagnosis, Computer-Assisted ; instrumentation ; methods ; Gene Expression Profiling ; methods ; Gene Regulatory Networks ; genetics ; Heart Diseases ; diagnosis ; Humans ; Models, Cardiovascular

Two kinds of algorithm have been set forth to estimate the symmetry characteristic of live human skull on CT image. These CT images were treated with a series of processes such as coding into programs, formatting originals, binary coding, rectifying image deviation, detecting boundary edge, and quantitatively measuring the skull symmetry. The statistical analyses of measuring 3000 live human skull images have worked out the ratio and the distribution of the skull symmetry, so that dependable data are provided for establishing the human head injury biomechanics model. The results are of great practical value in the fields of anatomy, clinical medicine, biomechanies study, head injury analysis, etc.
Biomechanical Phenomena ; Cephalometry ; methods ; Female ; Humans ; Image Processing, Computer-Assisted ; methods ; Male ; Reference Values ; Skull ; anatomy & histology ; diagnostic imaging ; Tomography, X-Ray Computed

Voxel based morphometry (VBM) methods are used to detect the difference in brain structures between the posttraumatic stress disorder (PTSD) sufferers and the normal controls. Standard VBM method can detect the difference of the gray matter or white matter densities while the optimized VBM method can detect the difference of gray matter or white matter volumes in the whole brain. The experiments showed that for the patient group, gray matter density or volumes significantly increased in the right frontal lobe, middle frontal gyrus, vermis, left caudate and parietal lobe, compared with the normal controls. However, in the left frontal lobe and middle frontal gyrus, gray matter density significantly decreased. There is no significant difference in white matter between the two groups. These results are consistent with those of the fMRI, which not only provide the evidence for further study of the pathogeny in PTSD but also validate the efficiency of the VBM methods for detecting the difference in the whole brain structure.
Adult ; Brain ; pathology ; Female ; Frontal Lobe ; pathology ; Humans ; Image Processing, Computer-Assisted ; Magnetic Resonance Imaging ; Male ; Parietal Lobe ; pathology ; Stress Disorders, Post-Traumatic ; pathology

The modeling of signal transduction pathways is a task of systems biology. However, such a task is very difficult because of the structure complexity, the strong nonlinearity of signaling pathways and the noised and incomplete measurements. The Levenberg-Marquardt algorithm (LM algorithm) is applied to estimate the unknown parameters of the signaling pathways. With this method, the identifiability of unknown parameters is appraised, and the sensitivity equations of original model are evaluated. Then we append the sensitivity equations to the original model in order to form the augmented model, and we apply the Levenberg-Marquardt algorithm to the augmented model in order to estimate parameters. TNFalpha mediated NF-kappaB signaling pathway is taken as an example to illustrate the effectiveness of this method, and the simulation results are given.
Algorithms ; Computer Simulation ; Humans ; Models, Theoretical ; NF-kappa B ; physiology ; Signal Transduction ; Systems Biology ; methods ; Tumor Necrosis Factor-alpha ; physiology