Ding Guanghong

Computational Fluid Dynamics Modeling of Intracranial Aneurysms

Hemodynamic factors like the wall shear stress (wss) play an important role in the pathogenesis and treatment of intracranial aneurysms. In this article, we applied computational fluid dynamic analysis on one patient-specific model of cerebral aneurysm and connected vessels constructed from 3D rotational angiography in order to understand the properties of blood flow around aneurysms and wall shear stress. Our whole simulation process is based on a series of CFD commercial software packages that is easy for clinicians to implement such method and use it in their daily practice. From the patient model analyzed in this investigation, we find that the comparatively maximum WSS occurs near the root of the aneurysm, which leads to damage in the aneurysmal wall, and the maximum displacement is at the peak of the aneurysm.

Displacement wave of the blood vessel —A mechanical model

According to clinical observations and model experiment, we have developed a theoretical model and obtained its mathematical equations to investigate the displacement wave of the blood vessel. The waveform and its occurrence criterion have been obtained by using perturbation theory and numerical method. The present study suggests that the displacement wave is associated with the blood velocity waveform and the machanical behaviour of the blood vessel, but not with the pressure waveform. The clinical criterion is in agreement with the observations.

SARS epidemical forecast research in mathematical model

The SIJR model, simplified from the SEIJR model, is adopted to analyze the important parameters of the model of SARS epidemic such as the transmission rate, basic reproductive number. And some important parameters are obtained such as the transmission rate by applying this model to analyzing the situation in Hong Kong, Singapore and Canada at the outbreak of SARS. Then forecast of the transmission of SARS is drawn out here by the adjustment of parameters (such as quarantined rate) in the model. It is obvious that inflexion lies on the crunode of the graph, which indicates the big difference in transmission characteristics between the epidemic under control and not under control. This model can also be used in the comparison of the control effectiveness among different regions. The results from this model match well with the actual data in Hong Kong, Singapore and Canada and as a by-product, the index of the effectiveness of control in the later period can be acquired. It offers some quantitative indexes, which may help the further research in epidemic diseases.

Dynamic principle for interaction between heart and arterial system

Various steady models for interaction between heart and arterial system have been given in literature. In our recent study, a dynamic principle, i.e. the principle of least cardiac work is proposed, and a dynamic model for interaction of heart and arterial system is established. Preliminary results of our experiments show that both the principle and the model are consistent with the physiological phenomena. It reveals that the present analysis may offer a new measure for the study of dynamic process of interaction between heart and arterial system.

Effect of warming moxibustion Tianshu (ST 25, bilateral) and Qihai (CV 6) for the treatment of diarrhea-dominant irritable bowel syndrome: a patient-blinded pilot trial with orthogonal design

Abstract Objective To investigate the effects of warming moxibustion Tianshu (ST 25, bilateral) and Qihai (CV 6) in patients with diarrhea-dominant irritable bowel syndrome (D-IBS) by assessing predominant factors, and determining the best factor combinations and their interactions. To identify the optimal quantity of warming moxibustion Tianshu (ST 25, bilateral) and Qihai (CV 6) to achieve optimal efficacy. Methods An L9 (3 4 ) orthogonal design was applied to 233 confirmed subjects based on the three most influential factors and the three most frequently used levels. Nine programs were designed. Subjects were assigned to four subgroups according to age and gender; each subject underwent one of the nine programs randomly. We selected Tianshu (ST 25, bilateral) and Qihai (CV 6). The scores of symptoms and the IBS Quality of Life (IBS-QOL) were evaluated after the final treatment. Results After treatment, clinical symptoms of all patients were significantly improved ( P = 0.001). Quality of life also improved significantly ( P P = 0.01). Duration was the dominating factor for quality of life ( P = 0.0001). The best combination for improving symptoms in 30–40-year-old male and female patients was two courses of 10 min each once a day, and for 41–50-year-old male and female patients it was three courses of 10 min (males) or 30 min (females) twice a day. The best combination for quality of life was three courses of 20 min once a day. No interaction was found between frequency and course, or frequency and duration. Conclusion Warming moxibustion Tianshu (ST 25, bilateral) and Qihai (CV 6) is a promising therapy for D-IBS. To acquire optimal efficacy, the three main factors (duration, frequency and treatment course) of the warming moxibustion should reach a specific quantity and be combined appropriately.

Study on body surface infrared radiation spectrum of points of patients with hyperplasia of mammary gland

Objective: To compare the difference of body surface infrared radiation (IR) spectrum between the point Qimen (LR14), point Danzhong (CV17) and non-acupoint control point of patients with hyperplasia of mammary gland (HMG). Methods: Sixty-eight patients with HMG were enrolled in this trail. The infrared radiation spectrum of left and right point Qimen (LR14), point Danzhong (CV17) and control point were detected by the high-sensitive PHE201 body surface infrared spectrometer, the wavelength from 1.5 m to 16 m were used. Results: There were 49 wavelengths (3.50, 4.00, 4.50~16.00 m) among 59 detected wavelengths, the IR intensity of left point Qimen (LR14) was significantly higher than that of the control point (p<0.05). There were 48 wavelengths (1.75, 3.50, 4.00, 4.50~6.50, 7.00, 7.50~16.00 m) among 59 detected wavelengths, the IR intensity of right point Qimen (LR14) was significantly higher than that of the control point (p<0.05). There were 13 wavelengths ( 6.75~8.25, 9.00, 9.25, 9.75, 13.25~13.75 m) among 59 detected wavelengths, the IR intensity of point Danzhong (CV17) was significantly lower than that of the control point (p<0.05). Conclusion: The infrared radiation intensity of point Qimen (LR14) is higher than that of the control point, while the infrared radiation intensity of point Danzhong (CV17) is lower than that of the control point, which indicates that the deficiency and excess of qi and blood of points from different.

Difference of the Infrared Spectrum Radiated from the Acupoints on Human Bodies between Healthy Volunteers and Patients Suffering from Coronary Heart Disease

To see whether there exists a difference of the infrared radiation of acupoints between the healthy volunteer subjects and the patients. In 47 healthy volunteer subjects and 51 patients suffering from coronary heart disease, the infrared radiation of five acupoints was detected and a statistic comparison between the two groups was made. There exists an obvious statistic difference of the infrared radiation between the healthy volunteer subjects and the patients. The physiological information in human bodies could be reflected from the infrared radiation of acupoints and also a possible method was provided to dignose with the infrared radiation spectrum without touching the patients.